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93 results on '"Kooten, Rick"'

1. Review of Physics Results from the Tevatron: Heavy Flavor Physics

Author: Lewis, Jonathan and van Kooten, Rick
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: We present a review of heavy flavor physics results from the CDF and D0 Collaborations operating at the Fermilab Tevatron Collider. A summary of results from Run 1 is included, but we concentrate on legacy results of charm and $b$ physics from Run 2, including results up to Summer 2014., Comment: References added; text tweaked. Article submitted to the International Journal of Modern Physics A (IJMPA) as one of the seven chapters of the special issue on the "Review of Physics at the Tevatron", editor G. Bernardi. This article contains the chapter on the heavy flavor physics part of the review. 53 pages, 32 figures, 276 references
Published: 2014
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2. Higgs Physics at the Linear Collider

Author: Gunion, John F., Haber, Howard E., and Van Kooten, Rick
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract: We review the theory of Higgs bosons, with emphasis on the Higgs scalars of the Standard Model and its non-supersymmetric and supersymmetric extensions. After surveying the expected knowledge of Higgs boson physics after the Tevatron and LHC experimental programs, we examine in detail expectations for precision Higgs measurements at a future e+e- linear collider (LC). A comprehensive phenomenological profile can be assembled from LC Higgs studies (both in e+e- and gamma-gamma collisions). The Giga-Z option can provide important constraints and consistency checks for the theory of electroweak symmetry breaking., Comment: 98 pages, 33 figures, 2 tables, references updated and expanded, to appear in "Linear Collider Physics in the New Millennium," edited by K. Fujii, D. Miller and A. Soni (World Scientific). A copy of the paper with higher resolution figures may be obtained from http://scipp.ucsc.edu/~haber/lcbook/higgschapter.ps
Published: 2003

3. Bounding CPT Violation in the Neutral-B System

Author: Kostelecky, Alan and Van Kooten, Rick
Subjects: High Energy Physics - Phenomenology
Abstract: The feasibility of placing bounds on CPT violation from experiments with neutral-$B$ mesons is examined. We consider situations with uncorrelated mesons and ones with either unboosted or boosted correlated mesons. Analytical expressions valid for small T- and CPT-violating parameters are presented for time-dependent and time-integrated decay rates, and various relevant asymmetries are derived. We use Monte-Carlo simulations to model experimental conditions for a plausible range of CPT-violating parameters. The treatment uses realistic data incorporating background effects, resolutions, and acceptances for typical detectors at LEP, CESR, and the future $B$ factories. Presently, there are no bounds on CPT violation in the $B$ system. We demonstrate that limits of order 10\% on CPT violation can be obtained from data already extant, and we determine the CPT reach attainable within the next few years., Comment: accepted for publication in Physical Review D
Published: 1996
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4. Higgs Physics at the Linear Collider

Author: Gunion, John F., primary, Haber, Howard E., additional, and Van Kooten, Rick, additional
Published: 2005
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5. A study of spin alignment of $\rho(770)^{\pm}$ and $\omega(782)$ mesons in hadronic Z $^0$ decays

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., De Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Density matrix, Particle physics, Range (particle radiation), Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, Hadron, 01 natural sciences, Omega, Helicity, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment, Spin-½
Abstract: The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons.
Published: 2000
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6. Measurement of the W+W−γ cross-section and first direct limits on anomalous electroweak quartic gauge couplings

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Photon, 010308 nuclear & particles physics, Physics beyond the Standard Model, Electroweak interaction, FOS: Physical sciences, Photon energy, Lambda, 01 natural sciences, Measure (mathematics), High Energy Physics - Experiment, Standard Model, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, 010306 general physics, Particle Physics - Experiment, Energy (signal processing)
Abstract: A study of W+W- events accompanied by hard photon radiation produced in e+e- collisions at LEP is presented. Events consistent with two on-shell W-bosons and an isolated photon are selected from 183pb^-1 of data recorded at root{s}=189GeV. From these data, 17 W+W-gamma candidates are selected with photon energy greater than 10GeV, consistent with the Standard Model expectation. These events are used to measure the e+e- to W+W-gamma cross-section within a set of geometric and kinematic cuts; sigma{W+W-gamma} = 136+-37+-8 fb, where the first error is statistical and the second systematic. The photon energy spectrum is used to set the first direct, albeit weak, limits on possible anomalous contributions to the {W+ W- gamma gamma} and {W+ W- gamma Z0} vertices: -0.070GeV^{-2} < a_0/Lambda^2 < 0.070GeV^{-2}, -0.13GeV^{-2} < a_c/Lambda^2 < 0.19GeV^{-2}, -0.61GeV^{-2} < a_n/Lambda^2 < 0.57GeV^{-2}, where Lambda represents the energy scale for new physics., 23 pages, 6 figures, submitted to Phys. Letts. B
Published: 1999
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7. Measurement of the semileptonic branching ratio of charm hadrons produced in ${\rm Z}^0\to{\rm c\bar c}$ decays

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, Branching fraction, Hadron, 01 natural sciences, 0103 physical sciences, Charm (quantum number), 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment, Lepton
Abstract: The inclusive charm hadron semileptonic branching fractions B(c to e) and B(c to mu) in Z to ccbar events have been determined using 4.4 million hadronic Z decays collected with the OPAL detector at LEP. A charm-enriched sample is obtained by selecting events with reconstructed D*+- mesons. Using leptons found in the hemisphere opposite that of the D*+- mesons, the semileptonic branching fractions of charm hadrons are measured to be B(c to e) = 0.103 +-0.009 +0.009 -0.008 and B(c to mu) = 0.090 +-0.007 +0.007 -0.006 where the first errors are in each case statistical and the others systematic. Combining these measurements, an inclusive semileptonic branching fraction of charm hadrons of B(c to l) = 0.095 +-0.006 +0.007 -0.006 is obtained. The inclusive charm hadron semileptonic branching fractions B(c to e) and B(c to mu) in Z to ccbar events have been determined using 4.4 million hadronic Z decays collected with the OPAL detector at LEP. A charm-enriched sample is obtained by selecting events with reconstructed D*+- mesons. Using leptons found in the hemisphere opposite that of the D*+- mesons, the semileptonic branching fractions of charm hadrons are measured to be B(c to e) = 0.103 +-0.009 +0.009 -0.008 and B(c to mu) = 0.090 +-0.007 +0.007 -0.006 where the first errors are in each case statistical and the others systematic. Combining these measurements, an inclusive semileptonic branching fraction of charm hadrons of B(c to l) = 0.095 +-0.006 +0.007 -0.006 is obtained.
Published: 1999
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8. Review of physics results from the Tevatron: Heavy flavor physics

Author: Lewis, Jonathan, primary and Van Kooten, Rick, additional
Published: 2015
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9. The International Large Detector: Letter of Intent

Author: Abe, Toshinori, Abernathy, Jason M., Abramowicz, Halina, Adamus, Marek, Adeva, Bernardo, Afanaciev, Konstantin, Aguilar-Saavedra, Juan Antonio, Alabau Pons, Carmen, Albrecht, Hartwig, Andricek, Ladislav, Anduze, Marc, Aplin, Steve J., Arai, Yasuo, Asano, Masaki, Attie, David, Attree, Derek J., Burger, Jochen, Bailey, David, Balbuena, Juan Pablo, Ball, Markus, Ballin, James, Barbi, Mauricio, Barlow, Roger, Bartels, Christoph, Bartsch, Valeria, Bassignana, Daniela, Bates, Richard, Baudot, Jerome, Bechtle, Philip, Beck, Jeannine, Beckmann, Moritz, Bedjidian, Marc, Behnke, Ties, Belkadhi, Khaled, Bellerive, Alain, Bentvelsen, Stan, Bergauer, Thomas, Berggren, C.Mikael U., Bergholz, Matthias, Bernreuther, Werner, Besancon, Marc, Besson, Auguste, Bhattacharya, Sudeb, Bhuyan, Bipul, Biebel, Otmar, Bilki, Burak, Blair, Grahame, Blumlein, Johannes, Bo, Li, Boisvert, Veronique, Bondar, A., Bonvicini, Giovanni, Boos, Eduard, Boudry, Vincent, Bouquet, Bernard, Bouvier, Joel, Bozovic-Jelisavcic, Ivanka, Brient, Jean-Claude, Brock, Ian, Brogna, Andrea, Buchholz, Peter, Buesser, Karsten, Bulgheroni, Antonio, Butler, John, Buttar, Craig, Buzulutskov, A.F., Caccia, Massimo, Caiazza, Stefano, Calcaterra, Alessandro, Caldwell, Allen, Callier, Stephane L.C., Calvo Alamillo, Enrique, Campbell, Michael, Campbell, Alan J., Cappellini, Chiara, Carloganu, Cristina, Castro, Nuno, Castro Carballo, Maria Elena, Chadeeva, Marina, Chakraborty, Dhiman, Chang, Paoti, Charpy, Alexandre, Chen, Xun, Chen, Shaomin, Chen, Hongfang, Cheon, Byunggu, Choi, Suyong, Choudhary, B.C., Christen, Sandra, Ciborowski, Jacek, Ciobanu, Catalin, Claus, Gilles, Clerc, Catherine, Coca, Cornelia, Colas, Paul, Colijn, Auke, Colledani, Claude, Combaret, Christophe, Cornat, Remi, Cornebise, Patrick, Corriveau, Francois, Cvach, Jaroslav, Czakon, Michal, D'Ascenzo, Nicola, Da Silva, Wilfrid, Dadoun, Olivier, Dam, Mogens, Damerell, Chris, Danilov, Mikhail, Daniluk, Witold, Daubard, Guillaume, David, Dorte, David, Jacques, De Boer, Wim, De Groot, Nicolo, De Jong, Sijbrand, De Jong, Paul, De La Taille, Christophe, De Masi, Rita, De Roeck, Albert, Decotigny, David, Dehmelt, Klaus, Delagnes, Eric, Deng, Zhi, Desch, Klaus, Dieguez, Angel, Diener, Ralf, Dima, Mihai-Octavian, Dissertori, Gunther, Dixit, Madhu S., Dolezal, Zdenek, Dolgoshein, Boris A., Dollan, Ralph, Dorokhov, Andrei, Doublet, Philippe, Doyle, Tony, Doziere, Guy, Dragicevic, Marko, Drasal, Zbynek, Drugakov, Vladimir, Duarte Campderros, Jordi, Dulucq, Frederic, Dumitru, Laurentiu Alexandru, Dzahini, Daniel, Eberl, Helmut, Eckerlin, Guenter, Ehrenfeld, Wolfgang, Eigen, Gerald, Eklund, Lars, Elsen, Eckhard, Elsener, Konrad, Emeliantchik, Igor, Engels, Jan, Evrard, Christophe, Fabbri, Riccardo, Faber, Gerard, Faucci Giannelli, Michele, Faus-Golfe, Angeles, Feege, Nils, Feng, Cunfeng, Ferencei, Jozef, Fernandez Garcia, Marcos, Filthaut, Frank, Fleck, Ivor, Fleischer, Manfred, Fleta, Celeste, Fleury, Julien L., Fontaine, Jean-Charles, Foster, Brian, Fourches, Nicolas, Fouz, Mary-Cruz, Frank, Sebastian, Frey, Ariane, Frotin, Mickael, Fujii, Hirofumi, Fujii, Keisuke, Fujimoto, Junpei, Fujita, Yowichi, Fusayasu, Takahiro, Fuster, Juan, Gaddi, Andrea, Gaede, Frank, Galkin, Alexei, Galkin, Valery, Gallas, Abraham, Gallin-Martel, Laurent, Gamba, Diego, Gao, Yuanning, Garrido Beltran, Lluis, Garutti, Erika, Gastaldi, Franck, Gaur, Bakul, Gay, Pascal, Gellrich, Andreas, Genat, Jean-Francois, Gentile, Simonetta, Gerwig, Hubert, Gibbons, Lawrence, Ginina, Elena, Giraud, Julien, Giraudo, Giuseppe, Gladilin, Leonid, Goldstein, Joel, Gonzalez Sanchez, Francisco Javier, Gournaris, Filimon, Greenshaw, Tim, Greenwood, Z.D., Grefe, Christian, Gregor, Ingrid-Maria, Grenier, Gerald Jean, Gris, Philippe, Grondin, Denis, Grunewald, Martin, Grzelak, Grzegorz, Gurtu, Atul, Haas, Tobias, Haensel, Stephan, Hajdu, Csaba, Hallermann, Lea, Han, Liang, Hansen, Peter H., Hara, Takanori, Harder, Kristian, Hartin, Anthony, Haruyama, Tomiyoshi, Harz, Martin, Hasegawa, Yoji, Hauschild, Michael, He, Qing, Hedberg, Vincent, Hedin, David, Heinze, Isa, Helebrant, Christian, Henschel, Hans, Hensel, Carsten, Hertenberger, Ralf, Herve, Alain, Higuchi, Takeo, Himmi, Abdelkader, Hironori, Kazurayama, Hlucha, Hana, Hommels, Bart, Horii, Yasuyuki, Horvath, Dezso, Hostachy, Jean-Yves, Hou, Wei-Shu, Hu-Guo, Christine, Huang, Xingtao, Huppert, Jean Francois, Ide, Yasuhiro, Idzik, Marek, Iglesias Escudero, Carmen, Ignatenko, Alexandr, Igonkina, Olga, Ikeda, Hirokazu, Ikematsu, Katsumasa, Ikemoto, Yukiko, Ikuno, Toshinori, Imbault, Didier, Imhof, Andreas, Imhoff, Marc, Ingbir, Ronen, Inoue, Eiji, Ioannis, Giomataris, Ishikawa, Akimasa, Itagaki, Kennosuke, Ito, Kazutoshi, Itoh, Hideo, Iwabuchi, Masaya, Iwai, Go, Iwamoto, Toshiyuki, Jacosalem, Editha P., Jaramillo Echeverria, Richard, Jeans, Daniel T D., Jing, Fanfan, Jing, Ge, Jokic, Stevan, Jonsson, Leif, Jore, Matthieu, Jovin, Tatjana, Kafer, Daniela, Kajino, Fumiyoshi, Kamai, Yusuke, Kaminski, Jochen, Kamiya, Yoshio, Kaplan, Alexander, Kapusta, Frederic, Kar, Deepak, Karlen, Dean, Katayama, Nobu, Kato, Eriko, Kato, Yukihiro, Kaukher, Alexander, Kawagoe, Kiyotomo, Kawahara, Hiroki, Kawai, Masanori, Kawasaki, Takeo, Khan, Sameen Ahmed, Kieffer, Robert, Kielar, Eryk, Kiesenhofer, Wolfgang, Kiesling, Christian M., Killenberg, Martin, Kim, Donghee, Kim, Choong Sun, Kim, Guinyun, Kim, Hong Joo, Kim, Eun-Joo, Kim, Hyunok, Kim, Shinhong, Kircher, Francois, Kisielewska, Danuta, Kleinwort, Claus, Klimkovich, Tatsiana, Kluge, Hanna, Kluit, Peter Martin, Kobayashi, Makoto, Kobel, Michael, Kodama, Hideyo, Kodys, Peter, Koetz, U., Koffeman, Els, Kohriki, Takashi, Komamiya, Sachio, Kondou, Yoshinari, Korbel, Volker, Kotera, Katsushige, Krucker, Dirk, Kraml, Sabine, Krammer, Manfred, Krastev, Kaloyan, Krause, Bernward, Krautscheid, Thorsten, Kschioneck, Kirsten, Kuang, Yu-Ping, Kuhlmann, Jan, Kuroiwa, Hirotoshi, Kusano, Tomonori, Kvasnicka, Peter, Lacasta Llacer, Carlos, Lagorio, Eric, Laktineh, Imad, Lange, Wolfgang, Lebrun, Patrice, Lee, Jik, Lehner, Frank, Lesiak, Tadeusz, Levy, Aharon, Li, Bo, Li, Ting, Li, Yulan, Li, Hengne, Liang, Zuotang, Lima, Guilherme, Linde, Frank, Linssen, Lucie, Linzmaier, Diana, List, Benno, List, Jenny, Liu, Bo, Llopart Cudie, Xavier, Lohmann, Wolfgang, Lopez Virto, Amparo, Lozano, Manuel, Lu, Shaojun, Lucaci-Timoce, Angela Isabela, Lumb, Nick, Lundberg, Bjorn, Lutz, Pierre, Lutz, Benjamin, Lux, Thorsten, Luzniak, Pawel, Lyapin, Alexey, Ma, Wengan, Maczewski, Lukasz, Mader, Wolfgang F., Maity, Manas, Majumdar, Nayana, Majumder, Gobinda, Maki, Akihiro, Makida, Yasuhiro, Mamuzic, Judita, Marc, Dhellot, Marchesini, Ivan, Marcisovsky, Michal, Marias, Carlos, Marshall, John, Martens, Cornelius, Martin, Victoria J., Martin, Jean-Pierre, Martin-Chassard, Gisele, Martinez Rivero, Celso, Martyn, Hans-Ulrich, Mathez, Herve, Mathieu, Antoine, Matsuda, Takeshi, Matsunaga, Hiroyuki, Matsushita, Takashi, Mavromanolakis, Georgios, Mcdonald, Kirk T., Mereu, Paolo, Merk, Marcel, Merkin, Mikhail M., Meyer, Niels, Meyners, Norbert, Mihara, Satoshi, Miller, David J., Miller, Owen, Mitaroff, Winfried A., Miyamoto, Akiya, Miyata, Hitoshi, Mjornmark, Ulf, Mnich, Joachim, Monig, Klaus, Moll, Andreas, Moortgat-Pick, Gudrid A., Mora De Freitas, Paulo, Morel, Frederic, Moretti, Stefano, Morgunov, Vasily, Mori, Toshinori, Mori, Takashi, Morin, Laurent, Morozov, Sergey, Moser, Hans-Gunther, Moser, Fabian, Moya, David, Mudrinic, Mihajlo, Mukhopadhyay, Supratik, Murakami, Takeshi, Musa, Luciano, Musat, Gabriel, Nagamine, Tadashi, Nakamura, Isamu, Nakano, Eiichi, Nakashima, Kenichi, Nakayoshi, Kazuo, Nakazawa, Hideyuki, Nam, Shinwoo, Nam, Jiwoo, Nemecek, Stanislav, Niebuhr, Carsten, Niechciol, Marcus, Niezurawski, Piotr, Nishida, Shohei, Nishiyama, Miho, Nitoh, Osamu, Norbeck, Ed, Nozaki, Mitsuaki, O'Shea, Val, Ohlerich, Martin, Okada, Nobuchika, Olchevski, Alexander, Olivier, Bob, Oliwa, Krzysztof, Omori, Tsunehiko, Onel, Yasar, Ono, Hiroaki, Ono, Yoshimasa, Onuki, Yoshiyuki, Ootani, Wataru, Orava, Risto, Orlandea, Marius Ciprian, Oskarsson, Anders, Osland, Per, Ossetski, Dmitri, Osterman, Lennart, Padilla, Cristobal, Pandurovic, Mila, Park, Il Hung, Park, Hwanbae, Parkes, Chris, Patrick, Ghislain, Patterson, J.Ritchie, Pawlik, Bogdan, Pellegrini, Giulio, Pellegrino, Antonio, Peterson, Daniel, Petrov, Alexander, Pham, Thanh Hung, Piccolo, Marcello, Poeschl, Roman, Polak, Ivo, Popova, Elena, Postranecky, Martin, Prahl, Volker, Prudent, Xavier, Przysiezniak, Helenka, Puerta-Pelayo, Jesus, Qian, Wenbin, Quadt, Arnulf, Rarbi, Fatah-Ellah, Raspereza, Alexei, Ratti, Lodovico, Raux, Ludovic, Raven, Gerhard, Re, Valerio, Regler, Meinhard, Reinhard, Marcel, Renz, Uwe, Repain, Philippe, Repond, Jose, Richard, Francois, Riemann, Sabine, Riemann, Tord, Riera-Babures, Jordi, Riu, Imma, Robert, Kieffer, Robson, Aidan, Roloff, Philipp, Rosca, Aura, Rosemann, Christoph, Rosiek, Janusz, Rossmanith, Robert, Roth, Stefan, Royon, Christophe, Ruan, Manqi, Ruiz-Jimeno, Alberto, Rusinov, Vladimir, Ruzicka, Pavel, Ryzhikov, Dmitri, Saborido, Juan J., Sadeh, Iftach, Sailer, Andre, Saito, Masatoshi, Sakuma, Takayuki, Sanami, Toshiya, Sanuki, Tomoyuki, Sarkar, Sandip, Sasaki, Rei, Sato, Yutaro, Saveliev, Valeri, Savoy-Navarro, Aurore, Sawyer, Lee, Schafer, Oliver, Schalicke, Andreas, Schuler, K.Peter, Schade, Peter, Schaffran, Joern, Scheirich, Jan, Schlatter, Dieter, Schmidt, Ringo Sebastian, Schmitt, Sebastian, Schneekloth, Uwe, Schreiber, Heinz Juergen, Schultz-Coulon, Hans-Christian, Schumacher, Markus, Schumm, Bruce A., Schuwalow, Sergej, Schwierz, Rainer, Sefkow, Felix, Sefri, Rachid, Seguin-Moreau, Nathalie, Seidel, Katja, Sekaric, Jadranka, Sendai, Hiroshi, Settles, Ronald Dean, Shao, Ming, Shechtman, L.I., Shimazaki, Shoichi, Shumeiko, Nikolai, Sicho, Petr, Simon, Frank, Sinram, Klaus, Smiljanic, Ivan, Smiljkovic, Nebojsa, Smolik, Jan, Sobloher, Blanka, Soldner, Christian, Song, Kezhu, Sopczak, Andre, Speckmayer, Peter, Stenlund, Evert, Stockinger, Dominik, Stoeck, Holger, Strohmer, Raimund, Straessner, Arno, Stromhagen, Richard, Sudo, Yuji, Suehara, Taikan, Suekane, Fumihiko, Suetsugu, Yusuke, Sugimoto, Yasuhiro, Sugiyama, Akira, Sumisawa, Kazutaka, Suzuki, Shiro, Swientek, Krzysztof, Tabassam, Hajrah, Takahashi, Tohru, Takeda, Hiroshi, Takeshita, Tohru, Takubo, Yosuke, Tanabe, Tomohiko, Tanaka, Shuji, Tanaka, Ken-Ichi, Tanaka, Manobu, Tapprogge, Stefan, Tarkovsky, Evgueny I., Tauchi, Toshiaki, Tauchi, Kazuya, Telnov, Valery I., Teodorescu, Eliza, Thomson, Mark, Tian, Junping, Timmermans, Jan, Titov, Maxim P., Tokushuku, Katsuo, Tozuka, Shunsuke, Tsuboyama, Toru, Ueno, Koji, Ullan, Miguel, Uozumi, Satoru, Urakawa, Junji, Ushakov, Andriy, Ushiroda, Yutaka, Valentan, Manfred, Valin, Isabelle, Van Der Graaf, Harry, Van Doren, Brian, Van Kooten, Rick J., Vander Donckt, Muriel, Vanel, Jean-Charles, Vazquez Regueiro, Pablo, Verzocchi, Marco, Vescovi, Christophe, Videau, Henri L., Vila, Ivan, Vilasis-Cardona, Xavier, Vogel, Adrian, Volkenborn, Robert, Vos, Marcel, Voutsinas, Yorgos, Vrba, Vaclav, Vreeswijk, Marcel, Walsh, Roberval, Waltenberger, Wolfgang, Wang, Min-Zu, Wang, Yi, Wang, Xiaoliang, Wang, Qun, Wang, Meng, Ward, David R., Warren, Matthew, Watanabe, Minori, Watanabe, Takashi, Watson, Nigel K., Wattimena, Nanda, Wendt, Oliver, Wermes, Norbert, Weuste, Lars, Wichmann, Katarzyna, Wienemann, Peter, Wierba, Wojciech, Wilson, Graham W., Wilson, John A., Wing, Matthew, Winter, Marc, Wobisch, Markus, Worek, Malgorzata, Xella, Stefania, Xu, Zizong, Yamaguchi, Akira, Yamaguchi, Hiroshi, Yamamoto, Hitoshi, Yamaoka, Hiroshi, Yamashita, Satoru, Yamauchi, M., Yamazaki, Yuji, Yamouni, Mahfoud, Yan, Wenbiao, Yanagida, Koji, Yang, Haijun, Yang, Jongmann, Yang, Jin Min, Yang, Zhenwei, Yasu, Yoshiji, Yonamine, Ryo, Yoshida, Kohei, Yoshida, Takuo, Yoshioka, Tamaki, Yu, Chunxu, Yu, Intae, Yue, Qian, Zacek, Josef, Zalesak, Jaroslav, Zarnecki, Aleksander Filip, Zawiejski, Leszek, Zeitnitz, Christian, Zerwas, Dirk, Zeuner, Wolfram, Zhang, Yanxi, Zhang, Ziping, Zhang, Renyou, Zhang, Xueyao, Zhang, Zhiqing, Zhao, Jiawei, Zhao, Zhengguo, Zheng, Baojun, Zhong, Liang, Zhou, Yongzhao, Zhu, Xianglei, Zhu, Chengguang, Zomer, Fabian, and Zutshi, Vishnu
Subjects: Physics, Particle physics, Time projection chamber, Large Hadron Collider, International Linear Collider, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Detector, Particle accelerator, Magnetic detector, 01 natural sciences, law.invention, law, 0103 physical sciences, Physics::Accelerator Physics, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Lepton, Event reconstruction
Abstract: The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV, upgradeable to 1 TeV. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance. The design of ILD is driven by these requirements. Excellent calorimetry and tracking are combined to obtain the best possible overall event reconstruction, including the capability to reconstruct individual particles within jets for particle ow calorimetry. This requires excellent spatial resolution for all detector systems. A highly granular calorimeter system is combined with a central tracker which stresses redundancy and efficiency. In addition, efficient reconstruction of secondary vertices and excellent momentum resolution for charged particles are essential for an ILC detector. The interaction region of the ILC is designed to host two detectors, which can be moved into the beam position with a push-pull scheme. The mechanical design of ILD and the overall integration of subdetectors takes these operational condition s into account. The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV, upgradeable to 1 TeV. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance. The design of ILD is driven by these requirements. Excellent calorimetry and tracking are combined to obtain the best possible overall event reconstruction, including the capability to reconstruct individual particles within jets for particle ow calorimetry. This requires excellent spatial resolution for all detector systems. A highly granular calorimeter system is combined with a central tracker which stresses redundancy and efficiency. In addition, efficient reconstruction of secondary vertices and excellent momentum resolution for charged particles are essential for an ILC detector. The interaction region of the ILC is designed to host two detectors, which can be moved into the beam position with a push-pull scheme. The mechanical design of ILD and the overall integration of subdetectors takes these operational conditions into account.
Published: 2010
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10. Averages of b-hadron Properties as of Winter 2005

Author: Anikeev, K., Barberio, E., Chang, P., Gershon, T., Harr, R., Hocker, Andreas, Iijima, T., Kirkby, David P., Kowalewski, Robert V., Lehner, F., Limosani, A., Luth, V., Sakai, Y., Olivier Schneider, Schwanda, C., Smith, J., Stocchi, A., Trabelsi, K., Kooten, Rick J., and Weiser, C.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: This article reports world averages for measurements on b-hadron properties obtained by the Heavy Flavor Averaging Group (HFAG) using the available results as of winter 2005 conferences. In the averaging, the input parameters used in the various analyses are adjusted (rescaled) to common values, and all known correlations are taken into account. The averages include lifetimes, neutral meson mixing parameters, semileptonic decay parameters, rare decay branching fractions, and CP violation measurements. This article reports world averages for measurements on b-hadron properties obtained by the Heavy Flavor Averaging Group (HFAG) using the available results as of winter 2005 conferences. In the averaging, the input parameters used in the various analyses are adjusted (rescaled) to common values, and all known correlations are taken into account. The averages include lifetimes, neutral meson mixing parameters, semileptonic decay parameters, rare decay branching fractions, and CP violation measurements.
Published: 2005

11. Linear Collider Physics Resource Book for Snowmass 2001, 2: Higgs and Supersymmetry Studies

Author: Abe, T., Arkani-Hamed, N., Asner, David Mark, Baer, H., Bagger, Jonathan A., Balazs, Csaba, Baltay, C., Barker, T., Barklow, T., Barron, J., Baur, Ulrich J., Beach, R., Bellwied, R., Bigi, Ikaros I.Y., Blochinger, C., Boege, S., Bolton, T., Bower, G., Brau, James E., Breidenbach, Martin, Brodsky, Stanley J., Burke, David L., Burrows, Philip N., Butler, Joel N., Chakraborty, Dhiman, Cheng, Hsin-Chia, Chertok, Maxwell Benjamin, Choi, Seong-Youl, Cinabro, David, Corcella, Gennaro, Cordero, R.K., Danielson, N., Davoudiasl, Hooman, Dawson, S., Denner, Ansgar, Derwent, P., Diaz, Marco Aurelio, Dima, M., Dittmaier, Stefan, Dixit, M., Dixon, Lance J., Dobrescu, Bogdan A., Doncheski, M.A., Duckwitz, M., Dunn, J., Early, J., Erler, Jens, Feng, Jonathan L., Ferretti, C., Fisk, H.Eugene, Fraas, H., Freitas, A., Frey, R., Gerdes, David W., Gibbons, L., Godbole, R., Godfrey, S., Goodman, E., Gopalakrishna, Shrihari, Graf, N., Grannis, Paul D., Gronberg, Jeffrey Baton, Gunion, John F., Haber, Howard E., Han, Tao, Hawkings, Richard, Hearty, Christopher, Heinemeyer, Sven, Hertzbach, Stanley S., Heusch, Clemens A., Hewett, JoAnne L., Hikasa, K., Hiller, G., Hoang, Andre H., Hollebeek, Robert, Iwasaki, M., Jacobsen, Robert Gibbs, Jaros, John Alan, Juste, A., Kadyk, John A., Kalinowski, J., Kalyniak, P., Kamon, Teruki, Karlen, Dean, Keller, L, Koltick, D., Kribs, Graham D., Kronfeld, Andreas Samuel, Leike, A., Logan, Heather E., Lykken, Joseph D., Macesanu, Cosmin, Magill, Stephen R., Marciano, William Joseph, Markiewicz, Thomas W., Martin, S., Maruyama, T., Matchev, Konstantin Tzvetanov, Monig, Klaus, Montgomery, Hugh E., Moortgat-Pick, Gudrid A., Moreau, G., Mrenna, Stephen, Murakami, Brandon, Murayama, Hitoshi, Nauenberg, Uriel, Neal, H., Newman, B., Nojiri, Mihoko M., Orr, Lynne H., Paige, F., Para, A., Pathak, S., Peskin, Michael E., Plehn, Tilman, Porter, F., Potter, C., Prescott, C., Rainwater, David Landry, Raubenheimer, Tor O., Repond, J., Riles, Keith, Rizzo, Thomas Gerard, Ronan, Michael T., Rosenberg, L., Rosner, Jonathan L., Roth, M., Rowson, Peter C., Schumm, Bruce Andrew, Seppala, L., Seryi, Andrei, Siegrist, J., Sinev, N., Skulina, K., Sterner, K.L., Stewart, I., Su, S., Tata, Xerxes Ramyar, Telnov, Valery I., Teubner, Thomas, Tkaczyk, S., Turcot, Andre S., van Bibber, Karl A., Van Kooten, Rick J., Vega, R., Wackeroth, Doreen, Wagner, D., Waite, Anthony P., Walkowiak, Wolfgang, Weiglein, Georg, Wells, James Daniel, Wester, William Carl, III, Williams, B., Wilson, G., Wilson, R., Winn, D., Woods, M., Wudka, J., Yakovlev, Oleg I., Yamamoto, H., and Yang, Hai Jun
Subjects: High Energy Physics::Phenomenology, Physics::Accelerator Physics, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: This Resource Book reviews the physics opportunities of a next-generation e+e- linear collider and discusses options for the experimental program. Part 2 reviews the possible experiments on Higgs bosons and supersymmetric particles that can be done at a linear collider. This Resource Book reviews the physics opportunities of a next-generation e+e- linear collider and discusses options for the experimental program. Part 2 reviews the possible experiments on Higgs bosons and supersymmetric particles that can be done at a linear collider.
Published: 2001

12. Measurements of $R_{b}$, $A_{FB}^{b}$ and $A_{FB}^{c}$ in $e^{+}e^{-}$ Collisions at 130-189 GeV

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: The cross-section ratio Rb=sigma(e+e- to b-antib)/sigma(e+e- to q-antiq) andthe bottom and charm forward-backward asymmetries AFB^b and AFB^c are measuredusing event samples collected by the OPAL detector at centre-of-mass energiesbetween 130 and 189 GeV. Events with bottom quark production are selected witha secondary vertex tag, and a hemisphere charge algorithm is used to extractAFB^b. In addition, the bottom and charm asymmetries are measured using leptonsfrom semileptonic decays of heavy hadrons and pions from D*+ to D0pi+ decays.The results are in agreement with the Standard Model predictions. The cross-section ratio Rb=sigma(e+e- to b-antib)/sigma(e+e- to q-antiq) and the bottom and charm forward-backward asymmetries AFB^b and AFB^c are measured using event samples collected by the OPAL detector at centre-of-mass energies between 130 and 189 GeV. Events with bottom quark production are selected with a secondary vertex tag, and a hemisphere charge algorithm is used to extract AFB^b. In addition, the bottom and charm asymmetries are measured using leptons from semileptonic decays of heavy hadrons and pions from D*+ to D0pi+ decays. The results are in agreement with the Standard Model predictions.
Published: 2000

13. Z boson pair production in $e^{+}e^{-}$ collisions at $\sqrt{s}$ = 183 and 189 GeV

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Cammin, J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Gunther, P.O., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauke, A., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Hensel, C., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klein, K., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lawson, I., Layter, J.G., Leins, A., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tarem, S., Taylor, R.J., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: A study of Z boson pair production in e+e- annihilation at center-of-mass energies near 183 GeV and 189 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nu nubar), quark and lepton pairs, (q qbar l+l-, q qbar nu nubar) and the all-hadronic final state (q qbar q qbar) are considered. In all states with at least one Z boson decaying hadronically, q qbar and b bbar final states are considered separately using lifetime and event-shape tags, thereby improving the cross-section measurement. At sqrt(s) = 189 GeV the Z-pair cross section was measured to be 0.80 (+0.14-0.13, stat.) (+0.06-0.05, syst.) pb, consistent with the Standard Model prediction. At sqrt(s) = 183 GeV the 95.L. upper limit is 0.55 pb. Limits on anomalous ZZgamma and ZZZ couplings are derived. A study of Z boson pair production in e + e − annihilation at center-of-mass energies near 183 GeV and 189 GeV is reported. Final states containing only leptons, (ℓ + ℓ − ℓ + ℓ − and ℓ + ℓ − ν ν ), quark and lepton pairs, ( q q ℓ + ℓ − , q q ν ν ) and the all-hadronic final state ( q q q q ) are considered. In all states with at least one Z boson decaying hadronically, q q and b b final states are considered separately using lifetime and event-shape tags, thereby improving the cross-section measurement. At s =189 GeV the Z-pair cross section was measured to be 0.80 +0.14 −0.13 ( stat. ) +0.06 −0.05 ( syst. ) pb , consistent with the Standard Model prediction. At s =183 GeV the 95% C.L. upper limit is 0.55 pb . Limits on anomalous ZZ γ and ZZZ couplings are derived. A study of Z boson pair production in e+e- annihilation at center-of-mass energies near 183 GeV and 189 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nu nubar), quark and lepton pairs, (q qbar l+l-, q qbar nu nubar) and the all-hadronic final state (q qbar q qbar) are considered. In all states with at least one Z boson decaying hadronically, q qbar and b bbar final states are considered separately using lifetime and event-shape tags, thereby improving the cross-section measurement. At sqrt(s) = 189 GeV the Z-pair cross section was measured to be 0.80 (+0.14-0.13, stat.) (+0.06-0.05, syst.) pb, consistent with the Standard Model prediction. At sqrt(s) = 183 GeV the 95% C.L. upper limit is 0.55 pb. Limits on anomalous ZZgamma and ZZZ couplings are derived.
Published: 2000

14. Measurement of |$V_{cb}$| using $\overline{B}^{0} \to D^{*+}l^{-}\overline{\nu}$ decays

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Cammin, J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Gunther, P.O., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauke, A., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Hensel, C., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klein, K., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lawson, I., Layter, J.G., Leins, A., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tarem, S., Taylor, R.J., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: Particle Physics - Experiment
Abstract: The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb has been measured using B0 to D*l nu decays recorded on the Z0 peak using the OPAL detector at LEP. The D* to D0 pi+ decays were reconstructed both in the particular decay modes D0 to K- pi+ and D0 to K- pi+ pi- and via an inclusive technique. The product of |Vcb| and the decay form factor of the B0 to D* l nu transition at zero recoil F(1) was measured to be F(1)|Vcb| = (37.1+-1.0+-2.0)x10^-3, where the uncertainties are statistical and systematic respectively. By using Heavy Quark Effective Theory calculations for F(1), a value of |Vcb| = (40.7+-1.1+-2.2+-1.6)x 10^-3 was obtained, where the third error is due to theoretical uncertainties in the value of F(1). The branching ratio Br(B0 to D* l nu) was also measured to be (5.26+-0.20+-0.46) The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element V cb has been measured using B ̄ 0 → D ∗+ ℓ − ν ̄ decays recorded on the Z 0 peak using the OPAL detector at LEP. The D ∗+ → D 0 π + decays were reconstructed both in the particular decay modes D 0 →K − π + and D 0 →K − π + π 0 and via an inclusive technique. The product of | V cb | and the decay form factor of the B ̄ 0 → D ∗+ ℓ − ν ̄ transition at zero recoil F (1) was measured to be F (1)|V cb |=(37.1±1.0±2.0)×10 −3 , where the uncertainties are statistical and systematic respectively. By using Heavy Quark Effective Theory calculations for F (1) , a value of |V cb |=(40.7±1.1±2.2±1.6)×10 −3 was obtained, where the third error is due to theoretical uncertainties in the value of F (1) . The branching ratio Br( B ̄ 0 →D ∗+ ℓ − ν ̄ ) was also measured to be (5.26±0.20±0.46)%. The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb has been measured using B0 to D*l nu decays recorded on the Z0 peak using the OPAL detector at LEP. The D* to D0 pi+ decays were reconstructed both in the particular decay modes D0 to K- pi+ and D0 to K- pi+ pi- and via an inclusive technique. The product of |Vcb| and the decay form factor of the B0 to D* l nu transition at zero recoil F(1) was measured to be F(1)|Vcb| = (37.1+-1.0+-2.0)x10^-3, where the uncertainties are statistical and systematic respectively. By using Heavy Quark Effective Theory calculations for F(1), a value of |Vcb| = (40.7+-1.1+-2.2+-1.6)x 10^-3 was obtained, where the third error is due to theoretical uncertainties in the value of F(1). The branching ratio Br(B0 to D* l nu) was also measured to be (5.26+-0.20+-0.46)%.
Published: 2000

15. QCD studies with e+e- annihilation data at 172-189 GeV

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Cammin, J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Gunther, P.O., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauke, A., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Hensel, C., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klein, K., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lawson, I., Layter, J.G., Leins, A., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tarem, S., Taylor, R.J., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., Zer-Zion, D., G., Abbiendi, K., Ackerstaff, P. F., Akesson, G., Alexander, J., Allison, K. J., Anderson, S., Arcelli, S., Asai, S. F., Ashby, D., Axen, G., Azuelo, I., Bailey, A. H., Ball, E., Barberio, R. J., Barlow, J. R., Batley, S., Baumann, T., Behnke, K. W., Bell, G., Bella, A., Bellerive, S., Bentvelsen, S., Bethke, O., Biebel, A., Biguzzi, I. J., Bloodworth, P., Bock, J., Bohme, O., Boeriu, D., Bonacrosi, M., Boutemeur, S., Braibant, P., Bright Thoma, L., Brigliadori, R. M., Brown, H. J., Burckhart, J., Cammin, P., Capiluppi, R. K., Carnegie, A. A., Carter, J. R., Carter, C. Y., Chang, D. G., Charlton, D., Chrisman, C., Ciocca, P. E., L., E., Clay, I., Cohen, O. C., Cooke, J., Couchman, C., Couyoumtzeli, R. L., Coxe, M., Cuffiani, S., Dado, G. M., Dallavalle, S., Dallison, R., Davi, A., de Roeck, P., Dervan, K., Desch, B., Diene, M. S., Dixit, M., Donker, J., Dubbert, E., Duchovni, G., Duckeck, I. P., Duerdoth, P. G., Estabrook, E., Etzion, F., Fabbri, A., Fanfani, M., Fanti, A. A., Faust, L., Feld, P., Ferrari, F., Fiedler, M., Fierro, I., Fleck, A., Frey, A., Furtje, D. I., Futyan, P., Gagnon, J. W., Gary, G., Gaycken, C., Geich Gimbel, G., Giacomelli, P., Giacomelli, D. M., Gingrich, D., Glenzinski, J., Goldberg, W., Gorn, C., Grandi, K., Graham, E., Gro, J., Grunhau, M., Gruwe, P. O., Gunther, C., Hajdu, G. G., Hanson, M., Hansroul, M., Hapke, K., Harder, A., Harel, C. K., Hargrove, M., Harin Dirac, A., Hauke, M., Hauschild, C. M., Hawke, R., Hawking, R. J., Hemingway, C., Hensel, G., Herten, R. D., Heuer, M. D., Hildreth, J. C., Hill, P. R., Hobson, A., Hocker, K., Hoffman, R. J., Homer, A. K., Honma, D., Horvath, K. R., Hossain, R., Howard, P., Huntemeyer, P., Igo Kemene, D. C., Imrie, K., Ishii, F. R., Jacob, A., Jawahery, H., Jeremie, M., Jimack, C. R., Jone, P., Jovanovic, T. R., Junk, N., Kanaya, J., Kanzaki, G., Karapetian, D., Karlen, V., Kartvelishvili, K., Kawagoe, T., Kawamoto, P. I., Kayal, R. K., Keeler, R. G., Kellogg, B. W., Kennedy, D. H., Kim, K., Klein, A., Klier, T., Kobayashi, M., Kobel, T. P., Kokott, M., Kolrep, S., Komamiya, R. V., Kowalewski, T., Kre, P., Krieger, J., von Krogh, T., Kuhl, M., Kupper, P., Kyberd, G. D., Lafferty, H., Landsman, D., Lanske, I., Lawson, J. G., Layter, A., Lein, D., Lellouch, J., Lett, L., Levinson, R., Liebisch, J., Lillich, B., List, C., Littlewood, A. W., Lloyd, S. L., Lloyd, F. K., Loebinger, G. D., Long, M. J., Losty, J., Lu, J., Ludwig, A., Macchiolo, A., Macpherson, W., Mader, M., Mannelli, S., Marcellini, T. E., Marchant, A. J., Martin, J. P., Martin, G., Martinez, T., Mashimo, P., Mattig, W. J., Mcdonald, J., Mckenna, T. J., Mcmahon, R. A., Mcpherson, F., Meijer, P., Mendez Lorenzo, F. S., Merritt, H., Me, I., Meyer, A., Michelini, S., Mihara, G., Mikenberg, D. J., Miller, W., Mohr, A., Montanari, T., Mori, K., Nagai, I., Nakamura, H. A., Neal, R., Nisiu, S. W., O'Neale, F. G., Oakham, F., Odorici, H. O., Ogren, A., Okpara, M. J., Oreglia, S., Orito, G., Pasztor, J. R., Pater, G. N., Patrick, J., Patt, R., Perez Ochoa, P., Pfeifenschneider, J. E., Pilcher, J., Pinfold, D. E., Plane, B., Poli, J., Polok, M., Przybycien, A., Quadt, C., Rembser, H., Rick, S. A., Robin, N., Rodning, J. M., Roney, S., Rosati, K., Roscoe, A. M., Rossi, Y., Rozen, K., Runge, O., Runolfsson, D. R., Rust, K., Sach, T., Saeki, O., Sahr, W. M., Sang, E. K., G., C., Sbarra, A. D., Schaile, O., Schaile, P., Scharff Hansen, S., Schmitt, A., Schoning, M., Schroder, M., Schumacher, C., Schwick, W. G., Scott, R., Seuster, T. G., Shear, B. C., Shen, C. H., Shepherd Themistocleou, P., Sherwood, G. P., Siroli, A., Skuja, A. M., Smith, G. A., Snow, R., Sobie, S., Soldner Rembold, Spagnolo, Stefania Antonia, M., Sproston, A., Stahl, K., Stephen, K., Stoll, D., Strom, R., Strohmer, B., Surrow, S. D., Talbot, S., Tarem, R. J., Taylor, R., Teuscher, M., Thiergen, J., Thoma, M. A., Thomson, E., Torrence, S., Tower, T., Trefzger, I., Trigger, Z., Trocsanyi, E., Tsur, M. F., Turner Watson, I., Ueda, R., Van Kooten, P., Vannerem, M., Verzocchi, H., Vo, D., Waller, C. P., Ward, D. R., Ward, P. M., Watkin, A. T., Watson, N. K., Watson, P. S., Well, T., Wengler, N., Werme, D., Wetterling, J. S., White, G. W., Wilson, J. A., Wilson, T. R., Wyatt, S., Yamashita, V., Zacek, and D., Zer Zion
Subjects: Quantum chromodynamics, Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Hadron, Monte Carlo method, FOS: Physical sciences, 01 natural sciences, Charged particle, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Strong coupling, High Energy Physics::Experiment, Multiplicity (chemistry), 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment
Abstract: We have studied hadronic events from e+e- annihilation data at centre-of-mass energies of sqrt{s}=172, 183 and 189 GeV. The total integrated luminosity of the three samples, measured with the OPAL detector, corresponds to 250 pb^-1. We present distributions of event shape variables, charged particle multiplicity and momentum, measured separately in the three data samples. From these we extract measurements of the strong coupling alpha_s, the mean charged particle multiplicity and the peak position xi_0 in the xi_p=ln(1/x_p) distribution. In general the data are described well by analytic QCD calculations and Monte Carlo models. Our measured values of alpha_s, and xi_0 are consistent with previous determinations at sqrt{s}=MZ., Comment: 49 pages, 13 figures, submitted to Eur. Phys. J. C
Published: 2000

16. Search for new Physics in rare B Decays

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Cammin, J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Gunther, P.O., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauke, A., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Hensel, C., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klein, K., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lawson, I., Layter, J.G., Leins, A., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tarem, S., Taylor, R.J., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Branching fraction, Physics beyond the Standard Model, FOS: Physical sciences, 01 natural sciences, Standard Model, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, Limit (mathematics), 010306 general physics, Particle Physics - Experiment
Abstract: A search for the decay B+- to K+-K+-pi-+ was performed using data collected by the OPAL detector at LEP. These decays are strongly suppressed in the Standard Model but could occur with a higher branching ratio in supersymmetric models, especially in those with R-parity violating couplings. No evidence for a signal was observed and a 90% confidence level upper limit of 1.29x10^-4 was set for the branching ratio., Comment: 15 pages, 4 figures, to be published in Phys. Letts. B
Published: 2000
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17. Bose-Einstein correlations in $K^{\pm}K^{\pm}$ pairs from $Z^{0}$ decays into two hadronic jets

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Particle Physics - Experiment
Abstract: Bose-Einstein correlations in pairs of charged kaons produced in a sample of 3.9 million hadronic Z0 decays have been measured with the OPAL experiment at LEP. Charged kaons were identified in the central tracking detector using their specific energy loss in the drift chamber gas. The correlation function was studied in two-jet events using a double ratio, formed by the number of like-sign pairs normalised by a reference sample in the data, divided by the same ratio in a Monte Carlo simulation. The enhancement at small values of the four-momentum difference of the pair was parametrised using a Gaussian function. The parameters of the Bose-Einstein correlations were measured to be lambda = 0.82+-0.22(+0.17,-0.12) for the strength and R0 = 0.56+-0.08(+0.08, -0.06) fm for the kaon source radius, where the first errors are statistical and the second systematic. Corrections for final-state interactions are discussed. Bose-Einstein correlations in pairs of charged kaons produced in a sample of 3.9 million hadronic Z0 decays have been measured with the OPAL experiment at LEP. Charged kaons were identified in the central tracking detector using their specific energy loss in the drift chamber gas. The correlation function was studied in two-jet events using a double ratio, formed by the number of like-sign pairs normalised by a reference sample in the data, divided by the same ratio in a Monte Carlo simulation. The enhancement at small values of the four-momentum difference of the pair was parametrised using a Gaussian function. The parameters of the Bose-Einstein correlations were measured to be lambda = 0.82+-0.22(+0.17,-0.12) for the strength and R0 = 0.56+-0.08(+0.08,-0.06) fm for the kaon source radius, where the first errors are statistical and the second systematic. Corrections for final-state interactions are discussed.
Published: 1999

18. Search for Chargino and Neutralino Production at $\sqrt{s} = 189 GeV$ at LEP

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: A search for charginos and neutralinos, predicted by supersymmetric theories, is performed using a data sample of 182.1 pb-1 taken at a centre-of-mass energy of 189 GeV with the OPAL detector at LEP. No evidence for chargino or neutralino production is found. Upper limits on chargino and neutralino pair production cross-sections are obtained as a function of the chargino mass, the lightest neutralino mass and the second lightest neutralino mass. Within the Constrained Minimal Supersymmetric Standard Model framework, and for a chargino - neutralino mass difference of more than 5 GeV, the 95% confidence level lower limits on the chargino mass are 93.6 GeV for tan{beta} = 1.5 and 94.1 GeV for tan{beta} = 35. These limits are obtained assuming a universal scalar mass m_0 > 500 GeV. The corresponding limits for all m_0 are 78.0 and 71.7 GeV. The 95% confidence level lower limits on the lightest neutralino mass, valid for any value of tan{beta} are 32.8 GeV for m_0 > 500 GeV and 31.6 GeV for all m_0. A search for charginos and neutralinos, predicted by supersymmetric theories, is performed using a data sample of 182.1 pb-1 taken at a centre-of-mass energy of 189 GeV with the OPAL detector at LEP. No evidence for chargino or neutralino production is found. Upper limits on chargino and neutralino pair production cross-sections are obtained as a function of the chargino mass, the lightest neutralino mass and the second lightest neutralino mass. Within the Constrained Minimal Supersymmetric Standard Model framework, and for a chargino - neutralino mass difference of more than 5 GeV, the 95% confidence level lower limits on the chargino mass are 93.6 GeV for tan{beta} = 1.5 and 94.1 GeV for tan{beta} = 35. These limits are obtained assuming a universal scalar mass m_0 > 500 GeV. The corresponding limits for all m_0 are 78.0 and 71.7 GeV. The 95% confidence level lower limits on the lightest neutralino mass, valid for any value of tan{beta} are 32.8 GeV for m_0 > 500 GeV and 31.6 GeV for all m_0.
Published: 1999

19. Search for Anomalous Production of Acoplanar Di-lepton Events in $e^{+}e^{-}$ Collisions at $\sqrt{s}$=183 and 189 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: A selection of di-lepton events with significant missing transverse momentum has been performed using a total data sample of 237.4 pb-1 at e+e- centre-of-mass energies of 183 GeV and 189 GeV. The observed numbers of events - 78 at 183 GeV and 301 at 189 GeV - are consistent with the numbers expected from Standard Model processes, which arise predominantly from W+W- production with each W decaying leptonically. This topology is also an experimental signature for the pair production of new particles that decay to a charged lepton accompanied by one or more invisible particles. Discrimination techniques are described that optimise the sensitivity to particular new physics channels. No evidence for new phenomena is apparent and model independent limits are presented on the production cross-section times branching ratio squared for sleptons and for leptonically decaying charginos and charged Higgs. Assuming a 100 % branching ratio for the decay of a slepton to a lepton and the lightest neutralino, we exclude at 95 % CL: right-handed smuons with masses below 82.3 GeV for a smuon-neutralino mass difference > 3 Gev and right-handed staus with masses below 81.0 GeV for a stau-neutralino mass difference > 8 GeV. Right-handed selectrons are excluded at 95% CL for masses below 87.1 GeV for a selectron-neutralino mass diffeerence > 5GeV, within the framework of the Minimal Supersymmetric Standard Model assuming mu < -100 GeV and tan{beta} = 1.5. Charged Higgs bosons are excluded at 95% CL for masses below 82.8GeV, assuming a 100% branching ratio for their decay to tau+neutrino. A selection of di-lepton events with significant missing transverse momentum has been performed using a total data sample of 237.4 pb-1 at e+e- centre-of-mass energies of 183 GeV and 189 GeV. The observed numbers of events - 78 at 183 GeV and 301 at 189 GeV - are consistent with the numbers expected from Standard Model processes, which arise predominantly from W+W- production with each W decaying leptonically. This topology is also an experimental signature for the pair production of new particles that decay to a charged lepton accompanied by one or more invisible particles. Discrimination techniques are described that optimise the sensitivity to particular new physics channels. No evidence for new phenomena is apparent and model independent limits are presented on the production cross-section times branching ratio squared for sleptons and for leptonically decaying charginos and charged Higgs. Assuming a 100 % branching ratio for the decay of a slepton to a lepton and the lightest neutralino, we exclude at 95 % CL: right-handed smuons with masses below 82.3 GeV for a smuon-neutralino mass difference > 3 Gev and right-handed staus with masses below 81.0 GeV for a stau-neutralino mass difference > 8 GeV. Right-handed selectrons are excluded at 95% CL for masses below 87.1 GeV for a selectron-neutralino mass diffeerence > 5GeV, within the framework of the Minimal Supersymmetric Standard Model assuming mu < -100 GeV and tan{beta} = 1.5. Charged Higgs bosons are excluded at 95% CL for masses below 82.8GeV, assuming a 100% branching ratio for their decay to tau+neutrino.
Published: 1999

20. Search for Neutral Higgs Bosons in $e^{+}e^{-}$ Collisions at $\sqrt{s} \sim$ 189 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: A search for neutral Higgs bosons has been performed with the OPAL detector at LEP, using approximately 170 pb-1 of e+e- collision data collected at sqrt(s)~189GeV. Searches have been performed for the Standard Model (SM) process e+e- to H0Z0 and the MSSM processes e+e- to H0Z0, A0h0. The searches are sensitive to the b b-bar and tau antitau decay modes of the Higgs bosons, and also to the MSSM decay mode h0 to A0A0. OPAL search results at lower centre-of-mass energies have been incorporated in the limits we set, which are valid at the 95% confidence level. For the SM Higgs boson, we obtain a lower mass bound of 91.0 GeV. In the MSSM, our limits are mh>74.8GeV and mA>76.5GeV, assuming tan(beta)>1, that the mixing of the scalar top quarks is either zero or maximal, and that the soft SUSY-breaking masses are 1 TeV. For the case of zero scalar top mixing, we exclude values of tan(beta) between 0.72 and 2.19. A search for neutral Higgs bosons has been performed with the OPAL detector at LEP, using approximately 170 pb-1 of e+e- collision data collected at sqrt(s)~189GeV. Searches have been performed for the Standard Model (SM) process e+e- to H0Z0 and the MSSM processes e+e- to H0Z0, A0h0. The searches are sensitive to the b b-bar and tau antitau decay modes of the Higgs bosons, and also to the MSSM decay mode h0 to A0A0. OPAL search results at lower centre-of-mass energies have been incorporated in the limits we set, which are valid at the 95% confidence level. For the SM Higgs boson, we obtain a lower mass bound of 91.0 GeV. In the MSSM, our limits are mh>74.8GeV and mA>76.5GeV, assuming tan(beta)>1, that the mixing of the scalar top quarks is either zero or maximal, and that the soft SUSY-breaking masses are 1 TeV. For the case of zero scalar top mixing, we exclude values of tan(beta) between 0.72 and 2.19.
Published: 1999

21. Search for pair-produced leptoquarks in $e^{+}e^{-}$ interactions at $\sqrt{s} \simeq$ 183 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: A search for pair-produced leptoquarks has been performed using a sample of e+e- collision events collected by the OPAL detector at LEP at e+e- centre-of-mass energies of about 183 GeV. The data sample corresponds to an integrated luminosity of 55.9 pb-1. The leptoquarks were assumed to be produced via couplings to the photon and the Z0 and then to decay within a single fermion generation. No evidence for contributions from leptoquark pair production processes was observed. Lower limits on scalar and vector leptoquark masses are obtained. The existing limits are improved in the region of large decay branching ratio to quark-neutrino. A search for pair-produced leptoquarks has been performed using a sample of e+e- collision events collected by the OPAL detector at LEP at e+e- centre-of-mass energies of about 183 GeV. The data sample corresponds to an integrated luminosity of 55.9 pb-1. The leptoquarks were assumed to be produced via couplings to the photon and the Z0 and then to decay within a single fermion generation. No evidence for contributions from leptoquark pair production processes was observed. Lower limits on scalar and vector leptoquark masses are obtained. The existing limits are improved in the region of large decay branching ratio to quark-neutrino.
Published: 1999

22. Multi-photon production in $e^{+}e^{-}$ collisions at $\sqrt{s}$ = 189 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: The process e+e- to 2 (or 3) gammas is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb-1. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 304 GeV and Lambda- > 295 GeV as well as a mass limit for an excited electron, Me* > 306 GeV assuming equal e*egamma and eegamma couplings. Graviton exchange in the context of theories with higher dimensions is excluded for scales G+ < 660 GeV and G- < 634 GeV. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons and produced in association with another photon. The process e+e- to 2 (or 3) gammas is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb-1. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 304 GeV and Lambda- > 295 GeV as well as a mass limit for an excited electron, Me* > 306 GeV assuming equal e*egamma and eegamma couplings. Graviton exchange in the context of theories with higher dimensions is excluded for scales G+ < 660 GeV and G- < 634 GeV. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons and produced in association with another photon. The process e+e- to 2 (or 3) gammas is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb-1. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 304 GeV and Lambda- > 295 GeV as well as a mass limit for an excited electron, Me* > 306 GeV assuming equal e*egamma and eegamma couplings. Graviton exchange in the context of theories with higher dimensions is excluded for scales G+ < 660 GeV and G- < 634 GeV. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons and produced in association with another photon. The process e+e- to 2 (or 3) gammas is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb-1. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 304 GeV and Lambda- > 295 GeV as well as a mass limit for an excited electron, Me* > 306 GeV assuming equal e*egamma and eegamma couplings. Graviton exchange in the context of theories with higher dimensions is excluded for scales G+ < 660 GeV and G- < 634 GeV. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons and produced in association with another photon. The process e + e − → γγ ( γ ) is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb −1 . The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Λ + > 304 GeV and Λ − > 295 GeV as well as a mass limit for an excited electron, M e ∗ > 306 GeV assuming equal e ∗ eγ and eeγ couplings. Graviton exchange in the context of theories with higher dimensions is excluded for scales G + < 660 GeV and G − < 634 GeV. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons and produced in association with another photon.
Published: 1999

23. A study of $B^{0}_{s}$ meson oscillation using hadronic $Z^{0}$ decays containing leptons

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Lattice, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: A sample of Z decays containing b-flavoured hadrons is tagged using leptons, and events having precise proper time measurements are selected. These events are used to study Bs oscillations. using the lepton to tag the decay b-flavour and jet charge or a second lepton, where available, to determine the produced b-flavour. The flavour (b or b-bar) at decay is determined from the lepton charge while the flavour at production is determined from jet charge or the charge of a second lepton, where available. The experiment was not able to resolve the oscillatory behaviour, and we deduce that the Bs oscillation frequency Delta(ms)> 5.2ps-1 at the 95% confidence level. A sample of Z decays containing b-flavoured hadrons is tagged using leptons, and events having precise proper time measurements are selected. These events are used to study Bs oscillations. using the lepton to tag the decay b-flavour and jet charge or a second lepton, where available, to determine the produced b-flavour. The flavour (b or b-bar) at decay is determined from the lepton charge while the flavour at production is determined from jet charge or the charge of a second lepton, where available. The experiment was not able to resolve the oscillatory behaviour, and we deduce that the Bs oscillation frequency Delta(ms)> 5.2ps-1 at the 95% confidence level.
Published: 1999

24. Measurements of inclusive semileptonic branching fractions of b hadrons in $Z^{0}$ decays

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: A measurement of inclusive semileptonic branching fractions of b hadrons produced in Z decays is presented. An enriched Z -> bbbar sample is obtained with a lifetime flavour-tagging technique. The leptonic events are then selected from this sample, and classified according to their origin, which is determined by comparing the distribution of several kinematic variables using artificial neural network techniques. Using 3.6 million multihadronic events collected with the OPAL detector at energies near the Z resonance, the values BR(b->lX) =(10.83 +- 0.10(stat.) +- 0.20(syst.) +0.20 -0.13(model)) % BR(b->c->lX) = (8.40 +- 0.16(stat.) +- 0.21(syst.) +0.33 -0.29 (model)) % are measured, where b denotes all weakly decaying b hadrons and l represents either e or mu. The second error includes all experimental systematic uncertainties whereas the last error is due to uncertainties in modelling of the lepton momentum spectrum in semileptonic decays and b quark fragmentation. The average fraction of the beam energy carried by the weakly decaying b hadron, xe, is measured to be = 0.709 +- 0.003(stat.) +- 0.003 (syst.) +- 0.013(model) where the modelling error is dominated by the choice of b fragmentation model. The agreement between data and various semileptonic decay models and fragmentation functions is also investigated. A measurement of inclusive semileptonic branching fractions of b hadrons produced in Z decays is presented. An enriched Z -> bbbar sample is obtained with a lifetime flavour-tagging technique. The leptonic events are then selected from this sample, and classified according to their origin, which is determined by comparing the distribution of several kinematic variables using artificial neural network techniques. Using 3.6 million multihadronic events collected with the OPAL detector at energies near the Z resonance, the values BR(b->lX) =(10.83 +- 0.10(stat.) +- 0.20(syst.) +0.20 -0.13(model)) % BR(b->c->lX) = (8.40 +- 0.16(stat.) +- 0.21(syst.) +0.33 -0.29 (model)) % are measured, where b denotes all weakly decaying b hadrons and l represents either e or mu. The second error includes all experimental systematic uncertainties whereas the last error is due to uncertainties in modelling of the lepton momentum spectrum in semileptonic decays and b quark fragmentation. The average fraction of the beam energy carried by the weakly decaying b hadron, xe, is measured to be = 0.709 +- 0.003(stat.) +- 0.003 (syst.) +- 0.013(model) where the modelling error is dominated by the choice of b fragmentation model. The agreement between data and various semileptonic decay models and fragmentation functions is also investigated.
Published: 1999

25. Test of the Flavour Independence of $\alpha_{s}$ using Next-to-Leading Order Calculations for Heavy Quarks

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: We present a test of the flavour independence of the strong coupling constant for charm and bottom quarks with respect to light (uds) quarks, based on a hadronic event sample obtained with the OPAL detector at LEP. Five observables related to global event shapes were used to measure alpha_s in three flavour tagged samples (uds, c and b). The event shape distributions were fitted by Order(alpha_s**2) calculations of jet production taking into account mass effects for the c and b quarks. We find: = 0.997 +- 0.038(stat.) +- 0.030(syst.) +- 0.012(theory) and = 0.993 +- 0.008(stat.) +- 0.006(syst.) +- 0.011(theory) for the ratios alpha_s(charm)/alpha_s(uds) and alpha_s(b)/alpha_s(uds) respectively. We present a test of the flavour independence of the strong coupling constant for charm and bottom quarks with respect to light (uds) quarks, based on a hadronic event sample obtained with the OPAL detector at LEP. Five observables related to global event shapes were used to measure alpha_s in three flavour tagged samples (uds, c and b). The event shape distributions were fitted by Order(alpha_s**2) calculations of jet production taking into account mass effects for the c and b quarks. We find: = 0.997 +- 0.038(stat.) +- 0.030(syst.) +- 0.012(theory) and = 0.993 +- 0.008(stat.) +- 0.006(syst.) +- 0.011(theory) for the ratios alpha_s(charm)/alpha_s(uds) and alpha_s(b)/alpha_s(uds) respectively. We present a test of the flavour independence of the strong coupling constant for charm and bottom quarks with respect to light (uds) quarks, based on a hadronic event sample obtained with the OPAL detector at LEP. Five observables related to global event shapes were used to measure alpha_s in three flavour tagged samples (uds, c and b). The event shape distributions were fitted by Order(alpha_s**2) calculations of jet production taking into account mass effects for the c and b quarks. We find: = 0.997 +- 0.038(stat.) +- 0.030(syst.) +- 0.012(theory) and = 0.993 +- 0.008(stat.) +- 0.006(syst.) +- 0.011(theory) for the ratios alpha_s(charm)/alpha_s(uds) and alpha_s(b)/alpha_s(uds) respectively. We present a test of the flavour independence of the strong coupling constant for charm and bottom quarks with respect to light (uds) quarks, based on a hadronic event sample obtained with the OPAL detector at LEP. Five observables related to global event shapes were used to measure alpha_s in three flavour tagged samples (uds, c and b). The event shape distributions were fitted by Order(alpha_s**2) calculations of jet production taking into account mass effects for the c and b quarks. We find: = 0.997 +- 0.038(stat.) +- 0.030(syst.) +- 0.012(theory) and = 0.993 +- 0.008(stat.) +- 0.006(syst.) +- 0.011(theory) for the ratios alpha_s(charm)/alpha_s(uds) and alpha_s(b)/alpha_s(uds) respectively.
Published: 1999

26. Colour reconnection studies in $e^{+}e^{-} \to W^{+}W^{-}$ at $\sqrt{s}$=183 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hoch, M., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W+W- -> qqqq events with the non-leptonic component of W+W- -> qqlnu events. The scaled momentum distribution, its mean value, x_p, and that of the charged particle multiplicity, n_ch, are measured and found to be consistent in the two channels. The measured differences are: Diff(x_p) = +0.7 +- 0.8 +- 0.6 and Diff(n_ch) = (-0.09 +- 0.09 +-0.05)*10**-2. In addition, measurements of rapidity and thrust are performed for W+W- -> qqqq events. The data are described well by standard QCD models and disfavour one model of colour reconnection within the ARIADNE program. The current implementation of the ELLIS-GEIGER model of colour reconnection is excluded. At the current level of statistical precision no evidence for colour reconnection effects was found in the observables studied. The predicted effect of colour reconnection on OPAL measurements of M_W is also quantified in the context of models studied. The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W+W- -> qqqq events with the non-leptonic component of W+W- -> qqlnu events. The scaled momentum distribution, its mean value, x_p, and that of the charged particle multiplicity, n_ch, are measured and found to be consistent in the two channels. The measured differences are: Diff(x_p) = +0.7 +- 0.8 +- 0.6 and Diff(n_ch) = (-0.09 +- 0.09 +-0.05)*10**-2. In addition, measurements of rapidity and thrust are performed for W+W- -> qqqq events. The data are described well by standard QCD models and disfavour one model of colour reconnection within the ARIADNE program. The current implementation of the ELLIS-GEIGER model of colour reconnection is excluded. At the current level of statistical precision no evidence for colour reconnection effects was found in the observables studied. The predicted effect of colour reconnection on OPAL measurements of M_W is also quantified in the context of models studied. The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W+W- -> qqqq events with the non-leptonic component of W+W- -> qqlnu events. The scaled momentum distribution, its mean value, x_p, and that of the charged particle multiplicity, n_ch, are measured and found to be consistent in the two channels. The measured differences are: Diff(x_p) = +0.7 +- 0.8 +- 0.6 and Diff(n_ch) = (-0.09 +- 0.09 +-0.05)*10**-2. In addition, measurements of rapidity and thrust are performed for W+W- -> qqqq events. The data are described well by standard QCD models and disfavour one model of The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W+W- -> qqqq events with the non-leptonic component of W+W- -> qqlnu events. The scaled momentum distribution, its mean value, x_p, and that of the charged particle multiplicity, n_ch, are measured and found to be consistent in the two channels. The measured differences are: Diff(x_p) = +0.7 +- 0.8 +- 0.6 and Diff(n_ch) = (-0.09 +- 0.09 +-0.05)*10**-2. In addition, measurements of rapidity and thrust are performed for W+W- -> qqqq events. The data are described well by standard QCD models and disfavour one model of colour reconnection within the ARIADNE program. The current implementation of the ELLIS-GEIGER model of colour reconnection is excluded. At the current level of statistical precision no evidence for colour reconnection effects was found in the observables studied. The predicted effect of colour reconnection on OPAL measurements of M_W is also quantified in the context of models studied. The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W+W- -> qqqq events with the non-leptonic component of W+W- -> qqlnu events. The scaled momentum distribution, its mean value, x_p, and that of the charged particle multiplicity, n_ch, are measured and found to be consistent in the two channels. The measured differences are: Diff(x_p) = +0.7 +- 0.8 +- 0.6 and Diff(n_ch) = (-0.09 +- 0.09 +-0.05)*10**-2. In addition, measurements of rapidity and thrust are performed for W+W- -> qqqq events. The data are described well by standard QCD models and disfavour one model of colour reconnection within the ARIADNE program. The current implementation of the ELLIS-GEIGER model of colour reconnection is excluded. At the current level of statistical precision no evidence for colour reconnection effects was found in the observables studied. The predicted effect of colour reconnection on OPAL measurements of M_W is also quantified in the context of models studied. The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of s ≃182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W + W − → q q ′ q q ′ events with the non-leptonic component of W + W − → q q ′ ℓ ν ℓ events. The scaled momentum distribution, its mean value, 〈 x p 〉, and that of the charged particle multiplicity, 〈 n ch 〉, are measured and found to be consistent in the two channels. The measured differences are: Δ〈n ch 〉=〈n ch 4q 〉−2〈n ch qq ℓν 〉=+0.7±0.8±0.6 Δ〈x p 〉=〈x p 4q 〉−〈x p qq ℓν 〉=(−0.09±0.09±0.05)×10 −2 . In addition, measurements of rapidity and thrust are performed for W + W − → q q ′ q q ′ events. The data are described well by standard QCD models and disfavour one model of colour reconnection within the ARIADNE program. The current implementation of the Ellis-Geiger model of colour reconnection is excluded. At the current level of statistical precision no evidence for colour reconnection effects was found in the observables studied. The predicted effect of colour reconnection on OPAL measurements of M W is also quantified in the context of models studied.
Published: 1998

27. A Measurement of the Product Branching Ratio $f(b \to \Lambda_{b}).BR (\Lambda_{b} \to \Lambda X)$ in $Z^{0}$ Decays

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Darling, C., Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hoch, M., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Particle Physics - Experiment
Abstract: The product branching ratio, f(b->Lambda_b).BR(Lambda_b->Lambda X), where Lambda_b denotes any weakly-decaying b-baryon, has been measured using the OPAL detector at LEP. Lambda_b are selected by the presence of energetic Lambda particles in bottom events tagged by the presence of displaced secondary vertices. A fit to the momenta of the Lambda particles separates signal from B meson and fragmentation backgrounds. The measured product branching ratio is f(b->Lambda_b).BR(Lambda_b->Lambda X) = (2.67+-0.38(stat)+0.67-0.60(sy s))% Combined with a previous OPAL measurement, one obtains f(b->Lambda_b).BR(Lambda_b->Lambda X) = (3.50+-0.32(stat)+-0.35(sys ))%. The product branching ratio, f(b->Lambda_b).BR(Lambda_b->Lambda X), where Lambda_b denotes any weakly-decaying b-baryon, has been measured using the OPAL detector at LEP. Lambda_b are selected by the presence of energetic Lambda particles in bottom events tagged by the presence of displaced secondary vertices. A fit to the momenta of the Lambda particles separates signal from B meson and fragmentation backgrounds. The measured product branching ratio is f(b->Lambda_b).BR(Lambda_b->Lambda X) = (2.67+-0.38(stat)+0.67-0.60(sys))% Combined with a previous OPAL measurement, one obtains f(b->Lambda_b).BR(Lambda_b->Lambda X) = (3.50+-0.32(stat)+-0.35(sys))%.
Published: 1998

28. A measurement of the $\tau^{-} \to e^{-} \overline{\nu}_{e}\nu_{\tau}$ branching ratio

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hoch, M., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The branching ratio for the decay tau->e nue nutau has been measured using Z0 decay data collected by the OPAL experiment at LEP. In total 33073 tau->e nue nutau candidates were identified from a sample of 186197 selected tau decays, giving a branching ratio of 17.81 +- 0.09(stat) +_ 0.06(sys)%. This result is combined with other measurements to test e-mu and mu-tau universality in charged-current weak interactions. Additionally, the strong coupling constant alpha_s has been extracted and evolved to the Z0 mass scale, giving alpha_s = 0.1204 +- 0.0011(exp) +- 0.0019(theory). The branching ratio for the decay tau->e nue nutau has been measured using Z0 decay data collected by the OPAL experiment at LEP. In total 33073 tau->e nue nutau candidates were identified from a sample of 186197 selected tau decays, giving a branching ratio of 17.81 +- 0.09(stat) +_ 0.06(sys)%. This result is combined with other measurements to test e-mu and mu-tau universality in charged-current weak interactions. Additionally, the strong coupling constant alpha_s has been extracted and evolved to the Z0 mass scale, giving alpha_s = 0.1204 +- 0.0011(exp) +- 0.0019(theory). The branching ratio for the decay tau->e nue nutau has been measured using Z0 decay data collected by the OPAL experiment at LEP. In total 33073 tau->e nue nutau candidates were identified from a sample of 186197 selected tau decays, giving a branching ratio of 17.81 +- 0.09(stat) +_ 0.06(sys)%. This result is combined with other measurements to test e-mu and mu-tau universality in charged-current weak interactions. Additionally, the strong coupling constant alpha_s has been extracted and evolved to the Z0 mass scale, giving alpha_s = 0.1204 +- 0.0011(exp) +- 0.0019(theory). The branching ratio for the decay tau->e nue nutau has been measured using Z0 decay data collected by the OPAL experiment at LEP. In total 33073 tau->e nue nutau candidates were identified from a sample of 186197 selected tau decays, giving a branching ratio of 17.81 +- 0.09(stat) +_ 0.06(sys)%. This result is combined with other measurements to test e-mu and mu-tau universality in charged-current weak interactions. Additionally, the strong coupling constant alpha_s has been extracted and evolved to the Z0 mass scale, giving alpha_s = 0.1204 +- 0.0011(exp) +- 0.0019(theory). The branching ratio for the decay tau->e nue nutau has been measured using Z0 decay data collected by the OPAL experiment at LEP. In total 33073 tau->e nue nutau candidates were identified from a sample of 186197 selected tau decays, giving a branching ratio of 17.81 +- 0.09(stat) +_ 0.06(sys)%. This result is combined with other measurements to test e-mu and mu-tau universality in charged-current weak interactions. Additionally, the strong coupling constant alpha_s has been extracted and evolved to the Z0 mass scale, giving alpha_s = 0.1204 +- 0.0011(exp) +- 0.0019(theory). The branching ratio for the decay τ − → e − ν ̄ e ν τ has been measured using Z 0 decay data collected by the OPAL experiment at LEP. In total 33 073 τ − → e − ν ̄ e ν τ candidates were identified from a sample of 186 197 selected τ decays, giving a branching ratio of B (τ − → e − ν ̄ e ν τ )=(17.81±0.09 (stat) ±0.06 (syst) )% . This result is combined with other measurements to test e - μ and μ - τ universality in charged-current weak interactions. Additionally, the strong coupling constant α s ( m τ 2 ) has been extracted from B (τ − → e − ν ̄ e ν τ ) and evolved to the Z 0 mass scale, giving α s ( m Z 2 )=0.1204±0.0011 (exp)±0.0019 (theory).
Published: 1998

29. Bose-Einstein Correlations in $e^{+} e^{-} \to W^{+}W^{-}$ at 172 and 183 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., De Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hoch, M., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Condensed Matter::Quantum Gases, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Particle Physics - Experiment
Abstract: Bose-Einstein correlations between like-charge pions are studied in hadronic final states produced by e+e- annihilations at center-of-mass energies of 172 and 183 GeV. Three event samples are studied, each dominated by one of the processes W+W- to qqlnu, W+W- to qqqq, or (Z/g)* to qq. After demonstrating the existence of Bose-Einstein correlations in W decays, an attempt is made to determine Bose-Einstein correlations for pions originating from the same W boson and from different W bosons, as well as for pions from (Z/g)* to qq events. The following results are obtained for the individual chaoticity parameters lambda assuming a common source radius R: lambda_same = 0.63 +- 0.19 +- 0.14, lambda_diff = 0.22 +- 0.53 +- 0.14, lambda_Z = 0.47 +- 0.11 +- 0.08, R = 0.92 +- 0.09 +- 0.09. In each case, the first error is statistical and the second is systematic. At the current level of statistical precision it is not established whether Bose-Einstein correlations, between pions from different W bosons exist or not. Bose-Einstein correlations between like-charge pions are studied in hadronic final states produced by e+e- annihilations at center-of-mass energies of 172 and 183 GeV. Three event samples are studied, each dominated by one of the processes W+W- to qqlnu, W+W- to qqqq, or (Z/g)* to qq. After demonstrating the existence of Bose-Einstein correlations in W decays, an attempt is made to determine Bose-Einstein correlations for pions originating from the same W boson and from different W bosons, as well as for pions from (Z/g)* to qq events. The following results are obtained for the individual chaoticity parameters lambda assuming a common source radius R: lambda_same = 0.63 +- 0.19 +- 0.14, lambda_diff = 0.22 +- 0.53 +- 0.14, lambda_Z = 0.47 +- 0.11 +- 0.08, R = 0.92 +- 0.09 +- 0.09. In each case, the first error is statistical and the second is systematic. At the current level of statistical precision it is not established whether Bose-Einstein correlations, between pions from different W bosons exist or not.
Published: 1998

30. Search for Chargino and Neutralino Production at $\sqrt{s}$ = 181-184 GeV at LEP

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Lattice, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: A search for charginos and neutralinos, predicted by supersymmetric theories, has been performed using a data sample of 57 pb-1 at centre-of-mass energies of 181-184 GeV taken with the OPAL detector at LEP. No evidence for chargino or neutralino production has been found. Upper limits on chargino and neutralino pair production cross-sections are obtained as a function of the chargino mass, the lightest neutralino mass, and the second lightest neutralino mass. For large chargino masses the limits have been improved with respect to the previous analyses at lower centre-of-mass energies. Exclusion regions at 95% confidence level of parameters of the Constrained Minimal Supersymmetric Standard Model are determined for the case of a large universal scalar mass, m_0, implying heavy scalar fermions, and for the case of a small m_0 resulting in light scalar fermions and giving the worst-case limits. Within this framework and for the lightest chargino-neutralino mass difference greater than 5 GeV the 95% C.L. lower limits on the lightest chargino mass for m_0 = 500 GeV are 90.0 and 90.2 GeV for tan(beta) = 1.5 and 35 respectively. These limits for all m_0 (the worst-case) are 69.1 and 65.2 GeV for tan(beta) = 1.5 and 35 respectively. Exclusion regions are also presented for neutralino masses, including an absolute lower limit at 95% C.L. for the mass of the lightest neutralino of 30.1 GeV for m_0 = 500 GeV (24.2 GeV for all m_0), with implications for experimental searches for the lightest neutralino as a dark matter candidate. A search for charginos and neutralinos, predicted by supersymmetric theories, has been performed using a data sample of 57 pb-1 at centre-of-mass energies of 181-184 GeV taken with the OPAL detector at LEP. No evidence for chargino or neutralino production has been found. Upper limits on chargino and neutralino pair production cross-sections are obtained as a function of the chargino mass, the lightest neutralino mass, and the second lightest neutralino mass. For large chargino masses the limits have been improved with respect to the previous analyses at lower centre-of-mass energies. Exclusion regions at 95% confidence level of parameters of the Constrained Minimal Supersymmetric Standard Model are determined for the case of a large universal scalar mass, m_0, implying heavy scalar fermions, and for the case of a small m_0 resulting in light scalar fermions and giving the worst-case limits. Within this framework and for the lightest chargino-neutralino mass difference greater than 5 GeV the 95% C.L. lower limits on the lightest chargino mass for m_0 = 500 GeV are 90.0 and 90.2 GeV for tan(beta) = 1.5 and 35 respectively. These limits for all m_0 (the worst-case) are 69.1 and 65.2 GeV for tan(beta) = 1.5 and 35 respectively. Exclusion regions are also presented for neutralino masses, including an absolute lower limit at 95% C.L. for the mass of the lightest neutralino of 30.1 GeV for m_0 = 500 GeV (24.2 GeV for all m_0), with implications for experimental searches for the lightest neutralino as a dark matter candidate.
Published: 1998

31. Search for Anomalous Photonic Events with Missing Energy in $e^{+} e^{-}$ Collisions at $\sqrt{s}$ = 130, 136 and 183 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: Photonic events with large missing energy have been observed in e+e- collisions at centre-of-mass energies of 130, 136 and 183 GeV collected in 1997 using the OPAL detector at LEP. Results are presented for event topologies with a single photon and missing transverse energy or with an acoplanar photon pair. Cross-section measurements are performed within the kinematic acceptance of each selection. These results are compared with the expectations from the Standard Model process e+e- to nunubar + photon(s). No evidence is observed for new physics contributions to these final states. Using the data at Ecm = 183 GeV, upper limits on sigma(e+e- to X.Y)*BR(X to Y gamma) and sigma(e+e- to X.X)*BR(X to Y gamma)**2 are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos (X = nu*, Y = nu), to neutralino production (X = Chi_2^0, Y = Chi_1^0) and to supersymmetric models in which X = chi_1^0 and Y is a light gravitino. Photonic events with large missing energy have been observed in e+e- collisions at centre-of-mass energies of 130, 136 and 183 GeV collected in 1997 using the OPAL detector at LEP. Results are presented for event topologies with a single photon and missing transverse energy or with an acoplanar photon pair. Cross-section measurements are performed within the kinematic acceptance of each selection. These results are compared with the expectations from the Standard Model process e+e- to nunubar + photon(s). No evidence is observed for new physics contributions to these final states. Using the data at Ecm = 183 GeV, upper limits on sigma(e+e- to X.Y)*BR(X to Y gamma) and sigma(e+e- to X.X)*BR(X to Y gamma)**2 are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos (X = nu*, Y = nu), to neutralino production (X = Chi_2^0, Y = Chi_1^0) and to supersymmetric models in which X = chi_1^0 and Y is a light gravitino. Photonic events with large missing energy have been observed in $e^+ e^-$ collisions at centre-of-mass energies of 130, 136 and 183 GeV collected in 1997 using the OPAL detector at LEP. Results are presented for event topologies with a single photon and missing transverse energy or with an acoplanar photon pair. Cross-section measurements are performed within the kinematic acceptance of each selection. These results are compared with the expectations from the Standard Model process $e^+e^-$ $\rightarrow \nu \bar{\nu +}$ photon(s). No evidence is observed for new physics contributions to these final states. Using the data at $\sqrt{s} = 183$ GeV, upper limits on $\sigma$ ($e^+ e^-$ $\rightarrow$ X.Y)*BR(X $\to \textrm{Y}_{\gamma}$) and $\sigma$ ($e^+ e^-$ $\rightarrow$ X.X)*BR$^2$ (X $\to \textrm{Y}_{\gamma}$) are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos $(\textrm{X} = \nu^*, \textrm{Y} = \nu)$, to neutralino production $(\textrm{X} = \overline{\chi}^0_2, \textrm{Y} = \overline{\chi}^0_1)$ and to supersymmetric models in which $X = \overline{\chi}^0_1$ and $Y=\overline{\textrm{G}}$ is a light gravitino.
Published: 1998

32. A Measurement of $R_{b}$ using a Double Tagging Method

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., De Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The fraction of Z to bbbar events in hadronic Z decays has been measured by the OPAL experiment using the data collected at LEP between 1992 and 1995. The Z to bbbar decays were tagged using displaced secondary vertices, and high momentum electrons and muons. Systematic uncertainties were reduced by measuring the b-tagging efficiency using a double tagging technique. Efficiency correlations between opposite hemispheres of an event are small, and are well understood through comparisons between real and simulated data samples. A value of Rb = 0.2178 +- 0.0011 +- 0.0013 was obtained, where the first error is statistical and the second systematic. The uncertainty on Rc, the fraction of Z to ccbar events in hadronic Z decays, is not included in the errors. The dependence on Rc is Delta(Rb)/Rb = -0.056*Delta(Rc)/Rc where Delta(Rc) is the deviation of Rc from the value 0.172 predicted by the Standard Model. The result for Rb agrees with the value of 0.2155 +- 0.0003 predicted by the Standard Model. The fraction of Z to bbbar events in hadronic Z decays has been measured by the OPAL experiment using the data collected at LEP between 1992 and 1995. The Z to bbbar decays were tagged using displaced secondary vertices, and high momentum electrons and muons. Systematic uncertainties were reduced by measuring the b-tagging efficiency using a double tagging technique. Efficiency correlations between opposite hemispheres of an event are small, and are well understood through comparisons between real and simulated data samples. A value of Rb = 0.2178 +- 0.0011 +- 0.0013 was obtained, where the first error is statistical and the second systematic. The uncertainty on Rc, the fraction of Z to ccbar events in hadronic Z decays, is not included in the errors. The dependence on Rc is Delta(Rb)/Rb = -0.056*Delta(Rc)/Rc where Delta(Rc) is the deviation of Rc from the value 0.172 predicted by the Standard Model. The result for Rb agrees with the value of 0.2155 +- 0.0003 predicted by the Standard Model. The fraction of Z to bbbar events in hadronic Z decays has been measured by the OPAL experiment using the data collected at LEP between 1992 and 1995. The Z to bbbar decays were tagged using displaced secondary vertices, and high momentum electrons and muons. Systematic uncertainties were reduced by measuring the b-tagging efficiency using a double tagging technique. Efficiency correlations between opposite hemispheres of an event are small, and are well understood through comparisons between real and simulated data samples. A value of Rb = 0.2178 +- 0.0011 +- 0.0013 was obtained, where the first error is statistical and the second systematic. The uncertainty on Rc, the fraction of Z to ccbar events in hadronic Z decays, is not included in the errors. The dependence on Rc is Delta(Rb)/Rb = -0.056*Delta(Rc)/Rc where Delta(Rc) is the deviation of Rc from the value 0.172 predicted by the Standard Model. The result for Rb agrees with the value of 0.2155 +- 0.0003 predicted by the Standard Model.
Published: 1998

33. Multi-photon production in $e^{+}e^{-}$ collisions at $\sqrt{s}$= 183 GeV

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schorner, T., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 233 GeV and Lambda- > 265 GeV as well as a mass limit for an excited electron, M(e*) > 227 GeV assuming equal e*egamma and eegamma couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons. The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 233 GeV and Lambda- > 265 GeV as well as a mass limit for an excited electron, M(e*) > 227 GeV assuming equal e*egamma and eegamma couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons. The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 233 GeV and Lambda- > 265 GeV as well as a mass limit for an excited electron, M(e*) > 227 GeV assuming equal e*egamma and eegamma couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons. The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 233 GeV and Lambda- > 265 GeV as well as a mass limit for an excited electron, M(e*) > 227 GeV assuming equal e*egamma and eegamma couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons. The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 233 GeV and Lambda- > 265 GeV as well as a mass limit for an excited electron, M(e*) > 227 GeV assuming equal e*egamma and eegamma couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons. The process e + e − → γγ ( γ ) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb −1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Λ + > 233 GeV and Λ − > 265 GeV as well as a mass limit for an excited electron, M e ∗ > 227 GeV assuming equal e ∗ eγ and eeγ couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons.
Published: 1998

34. Di-Jet Production in Photon-Photon Collisions at $\sqrt{s}_{ee}$ = 161 and 172 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barillari, T., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., De Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Particle physics, Photon, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Monte Carlo method, Perturbative QCD, Parton, Jet (particle physics), 01 natural sciences, 0103 physical sciences, Rapidity, High Energy Physics::Experiment, Center of mass, 010306 general physics, Engineering (miscellaneous), Event (particle physics), Particle Physics - Experiment
Abstract: Di-jet production is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies 161 and 172 GeV. The jets are reconstructed using a cone jet finding algorithm. The angular distributions of direct and double-resolved processes are measured and compared to the predictions of leading order and next-to-leading order perturbative QCD. The jet energy profiles are also studied. The inclusive two-jet cross-section is measured as a function of transverse energy and rapidity and compared to next-to-leading order perturbative QCD calculations. The inclusive two-jet cross-section as a function of rapidity is compared to the prediction of the leading order Monte Carlo generators PYTHIA and PHOJET. The Monte Carlo predictions are calculated with different parametrisations of the parton distributions of the photon. The influence of the `underlying event' has been studied to reduce the model dependence of the predicted jet cross-sections from the Monte Carlo generators. Di-jet production is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies 161 and 172 GeV. The jets are reconstructed using a cone jet finding algorithm. The angular distributions of direct and double-resolved processes are measured and compared to the predictions of leading order and next-to-leading order perturbative QCD. The jet energy profiles are also studied. The inclusive two-jet cross-section is measured as a function of transverse energy and rapidity and compared to next-to-leading order perturbative QCD calculations. The inclusive two-jet cross-section as a function of rapidity is compared to the prediction of the leading order Monte Carlo generators PYTHIA and PHOJET. The Monte Carlo predictions are calculated with different parametrisations of the parton distributions of the photon. The influence of the `underlying event' has been studied to reduce the model dependence of the predicted jet cross-sections from the Monte Carlo generators. Di-jet production is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies 161 and 172 GeV. The jets are reconstructed using a cone jet finding algorithm. The angular distributions of direct and double-resolved processes are measured and compared to the predictions of leading order and next-to-leading order perturbative QCD. The jet energy profiles are also studied. The inclusive two-jet cross-section is measured as a function of transverse energy and rapidity and compared to next-to-leading order perturbative QCD calculations. The inclusive two-jet cross-section as a function of rapidity is compared to the prediction of the leading order Monte Carlo generators PYTHIA and PHOJET. The Monte Carlo predictions are calculated with different parametrisations of the parton distributions of the photon. The influence of the `underlying event' has been studied to reduce the model dependence of the predicted jet cross-sections from the Monte Carlo generators.
Published: 1998

35. A Study of Parton Fragmentation in Hadronic $Z^{0}$ Decays Using $\Lambda \overline\Lambda$ Correlations

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., De Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schmitz, R.E., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The correlated production of Lambda and Lambdabar baryons has been studied using 4.3 million multihadronic Zo decays recorded with the OPAL detector at LEP. Di-lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the k_t algorithm. The distributions of rapidity differences from correlated Lambda-Lambdabar pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The JETSET model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of JETSET, the MOdified Popcorn Scenarium (MOPS), and also HERWIG do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers. The correlated production of Lambda and Lambdabar baryons has been studied using 4.3 million multihadronic Zo decays recorded with the OPAL detector at LEP. Di-lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the k_t algorithm. The distributions of rapidity differences from correlated Lambda-Lambdabar pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The JETSET model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of JETSET, the MOdified Popcorn Scenarium (MOPS), and also HERWIG do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers. The correlated production of Lambda and Lambdabar baryons has been studied using 4.3 million multihadronic Zo decays recorded with the OPAL detector at LEP. Di-lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the k_t algorithm. The distributions of rapidity differences from correlated Lambda-Lambdabar pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The JETSET model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of JETSET, the MOdified Popcorn Scenarium (MOPS), and also HERWIG do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers. The correlated production of Lambda and Lambdabar baryons has been studied using 4.3 million multihadronic Zo decays recorded with the OPAL detector at LEP. Di-lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the k_t algorithm. The distributions of rapidity differences from correlated Lambda-Lambdabar pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The JETSET model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of JETSET, the MOdified Popcorn Scenarium (MOPS), and also HERWIG do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers.
Published: 1998

36. Inclusive production of charged hadrons and $K_{s}^{0}$ mesons in photon-photon collisions

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., De Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schorner, T., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wiesler, T., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Nuclear Theory, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: The production of charged hadrons and K_s mesons in the collisions of quasi-real photons has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass energies of 161 and 172 GeV. The differential cross-sections as a function of the transverse momentum and the pseudorapidity of the charged hadrons and K_s mesons have been compared to the leading order Monte Carlo simulations of PHOJET and PYTHIA and to perturbative next-to-leading order (NLO) QCD calculations. The distributions have been measured in the range 10-125 GeV of the hadronic invariant mass W. By comparing the transverse momentum distribution of charged hadrons measured in gamma-gamma interactions with gamma-proton and meson-proton data we find evidence for hard photon interactions in addition to the purely hadronic photon interactions. The production of charged hadrons and K_s mesons in the collisions of quasi-real photons has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass energies of 161 and 172 GeV. The differential cross-sections as a function of the transverse momentum and the pseudorapidity of the charged hadrons and K_s mesons have been compared to the leading order Monte Carlo simulations of PHOJET and PYTHIA and to perturbative next-to-leading order (NLO) QCD calculations. The distributions have been measured in the range 10-125 GeV of the hadronic invariant mass W. By comparing the transverse momentum distribution of charged hadrons measured in gamma-gamma interactions with gamma-proton and meson-proton data we find evidence for hard photon interactions in addition to the purely hadronic photon interactions. The production of charged hadrons and K_s mesons in the collisions of quasi-real photons has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass energies of 161 and 172 GeV. The differential cross-sections as a function of the transverse momentum and the pseudorapidity of the charged hadrons and K_s mesons have been compared to the leading order Monte Carlo simulations of PHOJET and PYTHIA and to perturbative next-to-leading order (NLO) QCD calculations. The distributions have been measured in the range 10-125 GeV of the hadronic invariant mass W. By comparing the transverse momentum distribution of charged hadrons measured in gamma-gamma interactions with gamma-proton and meson-proton data we find evidence for hard photon interactions in addition to the purely hadronic photon interactions.
Published: 1998

37. Measurements of flavour dependent fragmentation functions in $Z^{0} \to q\overline{q}$ events

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., De Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schorner, T., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Lattice, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: Fragmentation functions for charged particles in Z -> qq(bar) events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed D* mesons and secondary vertices. The \xi_p = ln(1/x_E) distributions and the position of their maxima \xi_max are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks. Fragmentation functions for charged particles in Z -> qq(bar) events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed D* mesons and secondary vertices. The \xi_p = ln(1/x_E) distributions and the position of their maxima \xi_max are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks. Fragmentation functions for charged particles in Z -> qq(bar) events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed D* mesons and secondary vertices. The \xi_p = ln(1/x_E) distributions and the position of their maxima \xi_max are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks. Fragmentation functions for charged particles in Z -> qq(bar) events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed D* mesons and secondary vertices. The \xi_p = ln(1/x_E) distributions and the position of their maxima \xi_max are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks.
Published: 1998

38. An upper limit for the $\tau$-neutrino mass from $\tau \to 5\pi^{\pm} \nu_{\tau}$ decays

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., De Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Evans, H.G., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schorner, T., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: An upper limit for the tau-neutrino mass has been determined from the decay tau -> 5pi+- \nu_tau using data collected with the OPAL detector from 1991 to 1995 in e+e- collisions at \sqrt{s} ~ M_Z. A limit of 43.2 MeV at 95% CL is obtained using a two-dimensional method in the 5pi invariant mass and energy distribution from 22 selected events. Combining this result with OPAL's previously published measurement using tau+tau- -> 3h+- \bar{nu}_tau 3h-+ obtained. An upper limit for the tau-neutrino mass has been determined from the decay tau -> 5pi+- \nu_tau using data collected with the OPAL detector from 1991 to 1995 in e+e- collisions at \sqrt{s} ~ M_Z. A limit of 43.2 MeV at 95% CL is obtained using a two-dimensional method in the 5pi invariant mass and energy distribution from 22 selected events. Combining this result with OPAL's previously published measurement using tau+tau- -> 3h+- \bar{nu}_tau 3h-+ \nu_tau decays, a new combined limit of m_{nu_tau} < 27.6 MeV (95% CL) is obtained.
Published: 1998

39. Production of $K^{0}_{S}$ and $\Lambda$ in Quark and Gluon Jets from $Z^{0}$ Decay

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Evans, H.G., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J.A., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schorner, T., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The production of K^0_S mesons and Lambda baryons in quark and gluon jets has been investigated using two complementary techniques. In the first approach, which provides high statistical accuracy, jets were selected using different jet finding algorithms and ordered according to their energy. Production rates were determined taking into account the dependences of quark and gluon compositions as a function of jet energy as predicted by Monte Carlo models. Selecting three-jet events with the k_perp (Durham) jet finder (y_cut = 0.005), the ratios of K^0_S and Lambda production rates in gluon and quark jets relative to the mean charged particle multiplicity were found to be 1.10 +/- 0.02 +/- 0.02 and 1.41 +/- 0.04 +/- 0.04, respectively, where the first uncertainty is statistical and the second is systematic. In the second approach, a new method of identifying quark jets based on the collimation of energy flow around the jet axis is introduced and was used to anti-tag gluon jets in symmetric (Y-shaped) three-jet events. Using the cone jet finding algorithm with a cone size of 30 degrees, the ratios of relative production rates in gluon and quark jets were determined to be 0.94 +/- 0.07 +/- 0.07 for K^0_S and 1.18 +/- 0.10 +/- 0.17 for Lambda. The results of both analyses are compared to the predictions of Monte Carlo models. The production of K^0_S mesons and Lambda baryons in quark and gluon jets has been investigated using two complementary techniques. In the first approach, which provides high statistical accuracy, jets were selected using different jet finding algorithms and ordered according to their energy. Production rates were determined taking into account the dependences of quark and gluon compositions as a function of jet energy as predicted by Monte Carlo models. Selecting three-jet events with the k_perp (Durham) jet finder (y_cut = 0.005), the ratios of K^0_S and Lambda production rates in gluon and quark jets relative to the mean charged particle multiplicity were found to be 1.10 +/- 0.02 +/- 0.02 and 1.41 +/- 0.04 +/- 0.04, respectively, where the first uncertainty is statistical and the second is systematic. In the second approach, a new method of identifying quark jets based on the collimation of energy flow around the jet axis is introduced and was used to anti-tag gluon jets in symmetric (Y-shaped) three-jet events. Using the cone jet finding algorithm with a cone size of 30 degrees, the ratios of relative production rates in gluon and quark jets were determined to be 0.94 +/- 0.07 +/- 0.07 for K^0_S and 1.18 +/- 0.10 +/- 0.17 for Lambda. The results of both analyses are compared to the predictions of Monte Carlo models. The production of K^0_S mesons and Lambda baryons in quark and gluon jets has been investigated using two complementary techniques. In the first approach, which provides high statistical accuracy, jets were selected using different jet finding algorithms and ordered according to their energy. Production rates were determined taking into account the dependences of quark and gluon compositions as a function of jet energy as predicted by Monte Carlo models. Selecting three-jet events with the k_perp (Durham) jet finder (y_cut = 0.005), the ratios of K^0_S and Lambda production rates in gluon and quark jets relative to the mean charged particle multiplicity were found to be 1.10 +/- 0.02 +/- 0.02 and 1.41 +/- 0.04 +/- 0.04, respectively, where the first uncertainty is statistical and the second is systematic. In the second approach, a new method of identifying quark jets based on the collimation of energy flow around the jet axis is introduced and was used to anti-tag gluon jets in symmetric (Y-shaped) three-jet events. Using the cone jet finding algorithm with a cone size of 30 degrees, the ratios of relative production rates in gluon and quark jets were determined to be 0.94 +/- 0.07 +/- 0.07 for K^0_S and 1.18 +/- 0.10 +/- 0.17 for Lambda. The results of both analyses are compared to the predictions of Monte Carlo models.
Published: 1998

40. Investigation of CP violation in $B^{0} \to J/\psi K_{s}^{0}$ decays at LEP

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Evans, M., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., List, B., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rembser, C., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Sachs, K., Saeki, T., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Strohmer, R., Szymanski, P., Tafirout, R., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Utzat, P., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Particle Physics - Experiment
Abstract: An investigation of CP violation was performed using a total of 24 candidates for B^0 -> J/psi K^0_S decay, with a purity of about 60%. These events were selected from 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP. An analysis procedure, involving techniques to reconstruct the proper decay times and tag the produced b-flavours, B^0 or B^0(bar), has been developed to allow a first direct study of the time dependent CP asymmetry that, in the Standard Model, is sin(2beta). The result is sin(2beta) = 3.2_{-2.0}^{+1.8} +/- 0.5, where the first error is statistical and the second systematic. This result is used to determine probabilities for different values of sin(2beta) in the physical region from -1 to +1. An investigation of CP violation was performed using a total of 24 candidates for B^0 -> J/psi K^0_S decay, with a purity of about 60%. These events were selected from 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP. An analysis procedure, involving techniques to reconstruct the proper decay times and tag the produced b-flavours, B^0 or B^0(bar), has been developed to allow a first direct study of the time dependent CP asymmetry that, in the Standard Model, is sin(2beta). The result is sin(2beta) = 3.2_{-2.0}^{+1.8} +/- 0.5, where the first error is statistical and the second systematic. This result is used to determine probabilities for different values of sin(2beta) in the physical region from -1 to +1.
Published: 1998

41. Determination of the Production Rate of $D^{*0}$ Mesons and of the Ratio V/(V+P) in $Z^{0} \to c\overline{c}$ Decays

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Evans, M., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., List, B., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rembser, C., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Strohmer, R., Szymanski, P., Tafirout, R., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Utzat, P., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: In e^+e^- collisions at centre-of-mass energies around 91 GeV, D^*0 mesons have been reconstructed using data collected with the OPAL detector at LEP. The hadronisation fraction has been measured to be f(c -> D^*0) = 0.218 +/- 0.054 +/- 0.045 +/- 0.007, where the errors correspond to the statistical and systematic errors specific to this analysis, and to systematic uncertainties from externally measured branching fractions, respectively. Together with previous OPAL measurements of the hadron isation fractions of other charmed mesons, this value is used to investigate the relative production of observed vector and pseudoscalar charmed mesons in Z^0 -> cc(bar) decays. The production ratio production rate in hadronic Z^0 decays is presented. In e^+e^- collisions at centre-of-mass energies around 91 GeV, D^*0 mesons have been reconstructed using data collected with the OPAL detector at LEP. The hadronisation fraction has been measured to be f(c -> D^*0) = 0.218 +/- 0.054 +/- 0.045 +/- 0.007, where the errors correspond to the statistical and systematic errors specific to this analysis, and to systematic uncertainties from externally measured branching fractions, respectively. Together with previous OPAL measurements of the hadronisation fractions of other charmed mesons, this value is used to investigate the relative production of observed vector and pseudoscalar charmed mesons in Z^0 -> cc(bar) decays. The production ratio is determined to be P^eff_V = V/(V+P) = 0.57 +/- 0.05. The relative primary production of vector and pseudoscalar mesons, P^prim_V, is studied in the context of the production and decay of orbitally excited charmed resonances. The first measurement of the inclusive D^*+_s production rate in hadronic Z^0 decays is presented.
Published: 1998

42. Measurement of the w boson mass and $w^{+} w^{-}$ production and decay properties in $e^{+}e^{-}$ collisions at s**(1/2) = 172-GeV

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Beeston, C., Behnke, T., Bell, A.N., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bloomer, J.E., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Bouwens, B.T., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davies, R., De Jong, S., del Pozo, L.A., Desch, K., Dienes, B., Dixit, M.S., do Couto e Silva, E., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Edwards, J.E.G., Estabrooks, P.G., Evans, H.G., Evans, M., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ingram, M.R., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, G., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Morii, M., Muller, U., Mihara, S., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Pearce, M.J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rees, D.L., Rigby, D., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Ros, E., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Rylko, R., Sachs, K., Saeki, T., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schenk, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schultz-Coulon, H.C., Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Szymanski, P., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Utzat, P., Van Kooten, Rick J., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilkens, B., Wilson, G.W., Wilson, J.A., Wolf, G., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment
Abstract: This paper describes the measurement of the W boson mass, M_W, and decay width, Gamma_W, from the direct reconstruction of the invariant mass of its decay products in W pair events collected at a mean centre-of-mass energy of sqrt{s} = 172.12 GeV with the OPAL detector at LEP. Measurements of the W pair production cross-section, the W decay branching fractions and properties of the W decay final states are also described. A total of 120 candidate W^+W^- events has been selected for an integrated luminosity of 10.36 pb^-1. The W^+W^- production cross-section is measured to be sigma_WW = 12.3 +/- 1.3(stat.) +/- 0.3(syst.) pb, consistent with the Standard Model expectation. The W^+W^- -> qq(bar) l nu and W^+W^- -> qq(bar)qq(bar) final states are used to obtain a direct measurement of Gamma_W = 1.30^{+0.62}_{-0.55}(stat.) +/- 0.18(syst.) GeV. Assuming the Standard Model relation between M_W and Gamma_W, the W boson mass is measured to be M_W = 80.32 +/- 0.30(stat.) +/- 0.09(syst.) GeV. The event properties of the fully-hadronic decays of W^+W^- events are compared to those of the semi-leptonic decays. At the current level of precision there is no evidence for effects of colour reconnection in the observables studied. Combining data recorded by OPAL at sqrt{s} ~ 161-172 GeV, the W boson branching fraction to hadrons is determined to be 69.8^{+3.0}_{-3.2}(stat.) +/- 0.7(syst.)%, consistent with the prediction of the Standard Model. The combined mass measurement from direct reconstruction and from the W^+W^- production cross-sections measured at sqrt{s} ~ 161 and sqrt{s} ~ 172 GeV is M_W = 80.35 +/- 0.24(stat.) +/- 0.07(syst.) GeV. This paper describes the measurement of the W boson mass, M_W, and decay width, Gamma_W, from the direct reconstruction of the invariant mass of its decay products in W pair events collected at a mean centre-of-mass energy of sqrt{s} = 172.12 GeV with the OPAL detector at LEP. Measurements of the W pair production cross-section, the W decay branching fractions and properties of the W decay final states are also described. A total of 120 candidate W^+W^- events has been selected for an integrated luminosity of 10.36 pb^-1. The W^+W^- production cross-section is measured to be sigma_WW = 12.3 +/- 1.3(stat.) +/- 0.3(syst.) pb, consistent with the Standard Model expectation. The W^+W^- -> qq(bar) l nu and W^+W^- -> qq(bar)qq(bar) final states are used to obtain a direct measurement of Gamma_W = 1.30^{+0.62}_{-0.55}(stat.) +/- 0.18(syst.) GeV. Assuming the Standard Model relation between M_W and Gamma_W, the W boson mass is measured to be M_W = 80.32 +/- 0.30(stat.) +/- 0.09(syst.) GeV. The event properties of the fully-hadronic decays of W^+W^- events are compared to those of the semi-leptonic decays. At the current level of precision there is no evidence for effects of colour reconnection in the observables studied. Combining data recorded by OPAL at sqrt{s} ~ 161-172 GeV, the W boson branching fraction to hadrons is determined to be 69.8^{+3.0}_{-3.2}(stat.) +/- 0.7(syst.)%, consistent with the prediction of the Standard Model. The combined mass measurement from direct reconstruction and from the W^+W^- production cross-sections measured at sqrt{s} ~ 161 and sqrt{s} ~ 172 GeV is M_W = 80.35 +/- 0.24(stat.) +/- 0.07(syst.) GeV.
Published: 1998

43. W+W- production and triple gauge boson couplings at LEP energies up to 183 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., De Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hoch, M., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Vachon, B., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Gauge boson, Particle physics, Luminosity (scattering theory), Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Branching fraction, Hadron, FOS: Physical sciences, Fizikai tudományok, Lambda, 7. Clean energy, 01 natural sciences, High Energy Physics - Experiment, Standard Model, High Energy Physics - Experiment (hep-ex), Természettudományok, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment, Lepton, Boson
Abstract: A study of W-pair production in e+e- annihilations at Lep2 is presented, based on 877 W+W- candidates corresponding to an integrated luminosity of 57 pb-1 at sqrt(s) = 183 GeV. Assuming that the angular distributions of the W-pair production and decay, as well as their branching fractions, are described by the Standard Model, the W-pair production cross-section is measured to be 15.43 +- 0.61 (stat.) +- 0.26 (syst.) pb. Assuming lepton universality and combining with our results from lower centre-of-mass energies, the W branching fraction to hadrons is determined to be 67.9 +- 1.2 (stat.) +- 0.5 (syst.)%. The number of W-pair candidates and the angular distributions for each final state (qqlnu,qqqq,lnulnu) are used to determine the triple gauge boson couplings. After combining these values with our results from lower centre-of-mass energies we obtain D(kappa_g)=0.11+0.52-0.37, D(g^z_1)=0.01+0.13-0.12 and lambda=-0.10+0.13-0.12, where the errors include both statistical and systematic uncertainties and each coupling is determined setting the other two couplings to the Standard Model value. The fraction of W bosons produced with a longitudinal polarisation is measured to be 0.242+-0.091(stat.)+-0.023(syst.). All these measurements are consistent with the Standard Model expectations., Comment: 48 pages, LaTeX, including 13 eps or ps figures, submitted to European Physical Journal C
Published: 1998
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44. Measurements of the $B^{0}_s$ and $\Lambda^{0}_b$ lifetimes

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Evans, M., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., List, B., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rembser, C., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Sachs, K., Saeki, T., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Strohmer, R., Szymanski, P., Tafirout, R., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Utzat, P., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: This paper presents updated measurements of the lifetimes of the B^0_s meson and the \Lambda_b baryon using 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of B^0_s decays is obtained using D_s^- \ell^+ combinations, where the D_s^- is fully reconstructed in the in the \phi \ell^- \nu(bar) X decay mode. A sample of \Lambda_b decays is obtained using \Lambda_c^+ \ell^- combinations, where the \Lambda_c^+ is fully reconstructed in its decay to a p K^- \pi^+ final state and partially reconstructed in the \Lambda \ell^+ \nu X decay channel. From 172 +/- 28 D_s^- \tau(B^0_s) = 1.50 +0.16 -0.15 +/- 0.04 ps, where the errors are statistical and systematic, respectively. From the 129 measured lifetime \tau(\Lambda_b) = 1.29 +0.24 -0.22 +/- 0.06 ps, where the errors are statistical and systematic, respectively. This paper presents updated measurements of the lifetimes of the B^0_s meson and the \Lambda_b baryon using 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of B^0_s decays is obtained using D_s^- \ell^+ combinations, where the D_s^- is fully reconstructed in the \phi \pi^-, K^*0 K^- and K^- K^0_S decay channels and partially reconstructed in the \phi \ell^- \nu(bar) X decay mode. A sample of \Lambda_b decays is obtained using \Lambda_c^+ \ell^- combinations, where the \Lambda_c^+ is fully reconstructed in its decay to a p K^- \pi^+ final state and partially reconstructed in the \Lambda \ell^+ \nu X decay channel. From 172 +/- 28 D_s^- \ell^+ combinations attributed to B^0_s decays, the measured lifetime is \tau(B^0_s) = 1.50 +0.16 -0.15 +/- 0.04 ps, where the errors are statistical and systematic, respectively. From the 129 +\- 25 \Lamda_c^+ \ell^- combinations attributed to \Lambda_b decays, the measured lifetime \tau(\Lambda_b) = 1.29 +0.24 -0.22 This paper presents updated measurements of the lifetimes of the B^0_s meson and the \Lambda_b baryon using 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of B^0_s decays is obtained using D_s^- \ell^+ combinations, where the D_s^- is fully reconstructed in the \phi \pi^-, K^*0 K^- and K^- K^0_S decay channels and partially reconstructed in the \phi \ell^- \nu(bar) X decay mode. A sample of \Lambda_b decays is obtained using \Lambda_c^+ \ell^- combinations, where the \Lambda_c^+ is fully reconstructed in its decay to a p K^- \pi^+ final state and partially reconstructed in the \Lambda \ell^+ \nu X decay channel. From 172 +/- 28 D_s^- \ell^+ combinations attributed to B^0_s decays, the measured lifetime is \tau(B^0_s) = 1.50 +0.16 -0.15 +/- 0.04 ps, where the errors are statistical and systematic, respectively. From the 129 +\- 25 \Lamda_c^+ \ell^- combinations attributed to \Lambda_b decays, the measured lifetime \tau(\Lambda_b) = 1.29 +0.24 -0.22 +/- 0.06 ps, where the errors are statistical and systematic, respectively. This paper presents updated measurements of the lifetimes of the B s 0 meson and the Λ b 0 baryon using 4.4 million hadronic Z 0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of B s 0 decays is obtained using D s − ℓ + combinations, where the D s − is fully reconstructed in the φπ − , K ∗0 K − and K − K 0 S decay channels and partially reconstructed in the φℓ − ν ̄ X decay mode. A sample of Λ b 0 decays is obtained using Λ c + ℓ − combinations, where the Λ c + is fully reconstructed in its decay to a pK − π + final state and partially reconstructed in the Λ ℓ + ν X decay channel. From 172±28 D s − ℓ + combinations attributed to B s 0 decays, the measured lifetime is τ(B s 0 ) =1.50 +0.16 −0.15 ±0.04 ps , where the errors are statistical and systematic, respectively. From the 129±25 Λ c + ℓ − combinations attributed to Λ b 0 decays, the measured lifetime is τ( Λ b 0 ) =1.29 +0.24 −0.22 ±0.06 ps , where the errors are statistical and systematic, respectively.
Published: 1997

45. Search for anomalous production of photonic events with missing energy in $e^+ e^-$ collisions at $\sqrt{s}$ = 130-172 GeV

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Beeston, C., Behnke, T., Bell, A.N., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bloomer, J.E., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., Desch, K., Dienes, B., Dixit, M.S., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Edwards, J.E.G., Estabrooks, P.G., Evans, H.G., Evans, M., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ingram, M.R., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, G., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Muller, U., Mihara, S., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rembser, C., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Rylko, R., Sachs, K., Saeki, T., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schultz-Coulon, H.C., Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Strohmer, R., Szymanski, P., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Utzat, P., Van Kooten, Rick J., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilkens, B., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: Photonic events with large missing energy have been observed in e+e- collisions at centre-of-mass energies of 130, 136, 161 and 172 GeV using the OPAL detector at LEP. Results are presented based on search topologies designed to select events with a single photon and missing transverse energy or events with a pair of acoplanar photons. In both search topologies, cross-section measurements are performed within the kinematic acceptance of the selection. These results are compared with the expectations from the Standard Model processes e+e- -> nu nu(bar) gamma (gamma) (single-photon) and e+e- -> \nu new physics contributions to these final states. Upper limits on sigma(e+e- -> XY)*Br(X -> Y gamma) and sigma(e+e- -> XX)*Br**2(X -> Y gamma) are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos (X = \nu^*, Y = \nu), to neutralino production (X = \chi^0_2, Y = \chi^0_1), and to supersymmetric models in which X = results of the acoplanar-photons search are used to provide model-dependent lower limits on the mass of the lightest neutralino. Photonic events with large missing energy have been observed in e+e- collisions at centre-of-mass energies of 130, 136, 161 and 172 GeV using the OPAL detector at LEP. Results are presented based on search topologies designed to select events with a single photon and missing transverse energy or events with a pair of acoplanar photons. In both search topologies, cross-section measurements are performed within the kinematic acceptance of the selection. These results are compared with the expectations from the Standard Model processes e+e- -> nu nu(bar) gamma (gamma) (single-photon) and e+e- -> \nu \nu(bar) gamma gamma (gamma) (acoplanar-photons). No evidence is observed for new physics contributions to these final states. Upper limits on sigma(e+e- -> XY)*Br(X -> Y gamma) and sigma(e+e- -> XX)*Br**2(X -> Y gamma) are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos (X = \nu^*, Y = \nu), to neutralino production (X = \chi^0_2, Y = \chi^0_1), and to supersymmetric models in which X = \chi^0_1 and Y = \tilde{G} is a light gravitino. For the latter scenario, the results of the acoplanar-photons search are used to provide model-dependent lower limits on the mass of the lightest neutralino.
Published: 1997

46. Measurement of triple gauge boson couplings from $W^+ W^-$ production at $\sqrt{s}$ = 172 GeV

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Beeston, C., Behnke, T., Bell, A.N., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bloomer, J.E., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Bouwens, B.T., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., Desch, K., Dienes, B., Dixit, M.S., do Couto e Silva, E., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Edwards, J.E.G., Estabrooks, P.G., Evans, H.G., Evans, M., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ingram, M.R., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, G., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Morii, M., Muller, U., Mihara, S., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Pearce, M.J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rees, D.L., Rigby, D., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Ros, E., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Rylko, R., Sachs, K., Saeki, T., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schenk, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schultz-Coulon, H.C., Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Szymanski, P., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Utzat, P., Van Kooten, Rick J., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilkens, B., Wilson, G.W., Wilson, J.A., Wolf, G., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Particle Physics - Experiment
Abstract: We present measurements of triple gauge boson coupling parameters using data recorded by the OPAL detector at LEP2 at a centre-of-mass energy of 172 GeV. A total of 120 W-pair candidates has been selected in the q q(bar) q q(bar), q q(bar) l nu(bar)_l, and l nu(bar)_l l(bar)' nu_l' decay channels, for an integrated luminosity of 10.4 pb^-1. We use these data to determine several different anomalous coupling parameters using the measured cross-section and the distributions of kinematic variables. We measure alpha_B-phi = 0.35 + 1.29 - 1.07 +/- 0.38, alpha_W-phi = 0.00 + 0.30 - 0.28 +/- 0.11, alpha_W = 0.18 + 0.49 - 0.47 +/- 0.23, Delta(g_1^z) = -0.03 + 0.40 -0.37 +/- 0.14, Delta(kappa_gamma^(HISZ)) = 0.03 + 0.55 - 0.51 +/- 0.20, and Delta(kappa) = 0.03 + 0.49 - 0.46 +/- 0.21. Combining the alpha_W-phi result with our previous result obtained from the 161 GeV data sample we measure alpha_W-phi = -0.08 + 0.28 - 0.25 +/- 0.10. All of these measurements are consistent with the Standard Model. We present measurements of triple gauge boson coupling parameters using data recorded by the OPAL detector at LEP2 at a centre-of-mass energy of 172 GeV. A total of 120 W-pair candidates has been selected in the q q(bar) q q(bar), q q(bar) l nu(bar)_l, and l nu(bar)_l l(bar)' nu_l' decay channels, for an integrated luminosity of 10.4 pb^-1. We use these data to determine several different anomalous coupling parameters using the measured cross-section and the distributions of kinematic variables. We measure alpha_B-phi = 0.35 + 1.29 - 1.07 +/- 0.38, alpha_W-phi = 0.00 + 0.30 - 0.28 +/- 0.11, alpha_W = 0.18 + 0.49 - 0.47 +/- 0.23, Delta(g_1^z) = -0.03 + 0.40 -0.37 +/- 0.14, Delta(kappa_gamma^(HISZ)) = 0.03 + 0.55 - 0.51 +/- 0.20, and Delta(kappa) = 0.03 + 0.49 - 0.46 +/- 0.21. Combining the alpha_W-phi result with our previous result obtained from the 161 GeV data sample we measure alpha_W-phi = -0.08 + 0.28 - 0.25 +/- 0.10. All of these measurements are consistent with the Standard Model.
Published: 1997

47. Search for anomalous production of dilepton events with missing transverse momentum in $e^{+} e^{-}$ collisions at $\sqrt{s}$ = 161 and 172 GeV

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Beeston, C., Behnke, T., Bell, A.N., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bloomer, J.E., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Bouwens, B.T., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., Desch, K., Dienes, B., Dixit, M.S., do Couto e Silva, E., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Edwards, J.E.G., Estabrooks, P.G., Evans, H.G., Evans, M., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ingram, M.R., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, G., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Morii, M., Muller, U., Mihara, S., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Pearce, M.J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rees, D.L., Rigby, D., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Ros, E., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Rylko, R., Sachs, K., Saeki, T., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schenk, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schultz-Coulon, H.C., Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Szymanski, P., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Utzat, P., Van Kooten, Rick J., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilkens, B., Wilson, G.W., Wilson, J.A., Wolf, G., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: Events containing a pair of charged leptons and significant missing transverse momentum are selected from a data sample corresponding to a total integrated luminosity of 20.6 pb^-1 at centre-of-mass energies of 161 GeV and 172 GeV. The observed number of events, four at 161 GeV and nine at 172 GeV, is consistent with the number expected from Standard Model processes, predominantly arising from W+W- production with each W decaying leptonically. This topology is also an experimental signature for the pair production of new particles that decay to a charged lepton accompanied by one or more invisible particles. Further event selection criteria are described that optimise the sensitivity to particular new physics channels. No evidence for new phenomena is observed and limits on the production of scalar charged lepton pairs and other new particles are presented. Events containing a pair of charged leptons and significant missing transverse momentum are selected from a data sample corresponding to a total integrated luminosity of 20.6 pb^-1 at centre-of-mass energies of 161 GeV and 172 GeV. The observed number of events, four at 161 GeV and nine at 172 GeV, is consistent with the number expected from Standard Model processes, predominantly arising from W+W- production with each W decaying leptonically. This topology is also an experimental signature for the pair production of new particles that decay to a charged lepton accompanied by one or more invisible particles. Further event selection criteria are described that optimise the sensitivity to particular new physics channels. No evidence for new phenomena is observed and limits on the production of scalar charged lepton pairs and other new particles are presented.
Published: 1997

48. Multi-photon final states in $e^+ e^-$ collisions at $\sqrt{s}$ = 130-172 GeV

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Beeston, C., Behnke, T., Bell, A.N., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bloomer, J.E., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Bouwens, B.T., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davies, R., De Jong, S., del Pozo, L.A., Desch, K., Dienes, B., Dixit, M.S., do Couto e Silva, E., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Edwards, J.E.G., Estabrooks, P.G., Evans, H.G., Evans, M., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ingram, M.R., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, G., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Morii, M., Muller, U., Mihara, S., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Pearce, M.J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rees, D.L., Rigby, D., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Ros, E., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Rylko, R., Sachs, K., Saeki, T., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schenk, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schultz-Coulon, H.C., Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Szymanski, P., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Utzat, P., Van Kooten, Rick J., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilkens, B., Wilson, G.W., Wilson, J.A., Wolf, G., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The process e^+e^- -> gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 25.38 pb^{-1} taken at centre-of-mass energies of 130-172 GeV. The measured cross-sections agree well with the expectation from QED. In a combined fit using data from all centre-of-mass energies, the angular distribution is used to obtain improved limits on the cut-off parameters: Lambda_+ > 195 GeV and Lambda_- > 210 GeV (95% CL). In addition, limits on non-standard e^+e^-gamma couplings and contact interactions, as well as a 95% CL mass limit for an excited electron, M_{e^*} > 194 GeV for an e^+e^-gamma coupling kappa = 1, are determined. The process e^+e^- -> gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 25.38 pb^{-1} taken at centre-of-mass energies of 130-172 GeV. The measured cross-sections agree well with the expectation from QED. In a combined fit using data from all centre-of-mass energies, the angular distribution is used to obtain improved limits on the cut-off parameters: Lambda_+ > 195 GeV and Lambda_- > 210 GeV (95% CL). In addition, limits on non-standard e^+e^-gamma couplings and contact interactions, as well as a 95% CL mass limit for an excited electron, M_{e^*} > 194 GeV for an e^+e^-gamma coupling kappa = 1, are determined.
Published: 1997

49. Measurement of the quark to photon fragmentation function through the inclusive production of prompt photons in hadronic Z^0 decays

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barillari, T., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Beeston, C., Behnke, T., Bell, A.N., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bloomer, J.E., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Bouwens, B.T., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davies, R., De Jong, S., del Pozo, L.A., Desch, K., Dienes, B., Dixit, M.S., do Couto e Silva, E., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Edwards, J.E.G., Estabrooks, P.G., Evans, H.G., Evans, M., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ingram, M.R., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, G., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Morii, M., Muller, U., Mihara, S., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Pearce, M.J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rees, D.L., Rigby, D., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Ros, E., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Rylko, R., Sachs, K., Saeki, T., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schenk, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schultz-Coulon, H.C., Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Szymanski, P., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Utzat, P., Van Kooten, Rick J., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilkens, B., Wilson, G.W., Wilson, J.A., Wolf, G., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Quark, Particle physics, Photon, Physics and Astronomy (miscellaneous), Astrophysics::High Energy Astrophysical Phenomena, Hadron, FOS: Physical sciences, Physics::Optics, ELECTROWEAK COUPLINGS, 7. Clean energy, 01 natural sciences, High Energy Physics - Experiment, EVENTS, High Energy Physics - Experiment (hep-ex), MONTE-CARLO, SEARCH, 0103 physical sciences, Energy spectrum, Fragmentation function, FINAL-STATE PHOTONS, 010306 general physics, Nuclear Experiment, Engineering (miscellaneous), Quantum chromodynamics, Physics, 010308 nuclear & particles physics, Detector, scattering, High Energy Physics::Phenomenology, LEP, Z0 DECAYS, High Energy Physics::Experiment, EMISSION, E+ E ANNIHILATION, Particle Physics - Experiment, Production rate
Abstract: The inclusive production of prompt photons with energy above 10 GeV is measured using the OPAL detector in hadronic Z^0 decays at LEP. In contrast to previous measurements, the prompt photons were not required to be isolated. The production rate and energy spectrum are found to be in agreement with QCD predictions for the quark-to-photon fragmentation function., 23 pages, LaTeX, 6 eps figures included, submitted to Zeit. Phys. C
Published: 1997

50. A measurement of the $B^{0}_{s}$ lifetime using reconstructed $D^{-}_{s}$ mesons

Author: Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barillari, T., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Beeston, C., Behnke, T., Bell, A.N., Bell, Kenneth Watson, Bella, G., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bloomer, J.E., Bobinski, M., Bock, P., Bonacorsi, D., Boutemeur, M., Bouwens, B.T., Braibant, S., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Clarke, P.E.L., Cohen, I., Conboy, J.E., Cooke, O.C., Cuffiani, M., Dado, S., Dallapiccola, C., Dallavalle, G.Marco, Davies, R., De Jong, S., del Pozo, L.A., Desch, K., Dienes, B., Dixit, M.S., do Couto e Silva, E., Doucet, M., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Edwards, J.E.G., Estabrooks, P.G., Evans, H.G., Evans, M., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fischer, H.M., Fleck, I., Folman, R., Fong, D.G., Foucher, M., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Geddes, N.I., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Giacomelli, R., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Goodrick, M.J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Hargrove, C.K., Hart, P.A., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Hutchcroft, D.E., Igo-Kemenes, P., Imrie, D.C., Ingram, M.R., Ishii, K., Jawahery, A., Jeffreys, P.W., Jeremie, H., Jimack, M., Joly, A., Jones, C.R., Jones, G., Jones, M., Jost, U., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kirk, J., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kress, T., Krieger, P., von Krogh, J., Kyberd, P., Lafferty, G.D., Lahmann, R., Lai, W.P., Lanske, D., Lauber, J., Lautenschlager, S.R., Layter, J.G., Lazic, D., Lee, A.M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markus, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mikenberg, G., Miller, D.J., Mincer, A., Mir, R., Mohr, W., Montanari, A., Mori, T., Morii, M., Muller, U., Mihara, S., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oh, A., Oldershaw, N.J., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Pearce, M.J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Posthaus, A., Rees, D.L., Rigby, D., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rooke, A., Ros, E., Rossi, A.M., Routenburg, P., Rozen, Y., Runge, K., Runolfsson, O., Ruppel, U., Rust, D.R., Rylko, R., Sachs, K., Saeki, T., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schenk, P., Schieck, J., Schleper, P., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schultz-Coulon, H.C., Schumacher, M., Schwick, C., Scott, W.G., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skillman, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Springer, Robert Wayne, Sproston, M., Stephens, K., Steuerer, J., Stockhausen, B., Stoll, K., Strom, David M., Szymanski, P., Tafirout, R., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Utzat, P., Van Kooten, Rick J., Verzocchi, M., Vikas, P., Vokurka, E.H., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilkens, B., Wilson, G.W., Wilson, J.A., Wolf, G., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: High Energy Physics::Lattice, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: We report a measurement of the B^0_s meson lifetime from B_s^0 -> D^-_s X decays, where D_s^- mesons are reconstructed in the D_s^- -> phi pi^- and D_s^- -> K^{*0} K^- decay channels. From approximately 3.7 million hadronic Z^0 decays recorded by the OPAL detector at LEP a sample is selected containing 911 +/- 83 candidates, of which 519 +/- 136 are estimated to be from B_s^0 meson decays. Fitting the distribution of the distance from the beam spot to the decay vertex of the D_s^- candidates with an unbinned likelihood function we measure tau(B_s^0) = 1.72 + 0.20 - 0.19 + 0.18 - 0.17 ps, where the errors are statistical and systematic, respectively.
Published: 1997

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