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1. Inclusive charged hadron and K0 production in two-photon interactions

Author

J. Boyer, Darien Wood, G. J. Feldman, K. Hayes, D. Herrup, J. A. Jaros, G. H. Trilling, G. S. Abrams, D. Karlen, P. C. Rowson, D. Cords, F. Butler, L. Gladney, N. S. Lockyer, G. Gidal, I. Juricic, M. S. Gold, J. Haggerty, A. M. Boyarski, M. L. Perl, R. A. Ong, K. Riles, Andrew Lankford, R. J. Hollebeek, D. Amidei, B. W. Leclaire, Michael Levi, V. Lüth, Mark E. Nelson, Gordon H. Hanson, J. A. Kadyk, J. M. Yelton, D. L. Burke, W. B. Schmidke, J. M. Dorfan, T. Schaad, H. Schellman, W. R. Innes, Patricia R. Burchat, G. Goldhaber, R. R. Larsen, A. Baden, and T. Barklow

Subjects
Quark, Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Pair production, Annihilation, Meson, Hadron, Elementary particle, Production (computer science), Fermion
Abstract

The analogous process to quark pair production in e{sup +} e{sup {minus}} annihilation is the hard-scattering quark exchange process in {gamma}{gamma} interactions. This hard-scattering process is expected to dominate the cross section at high transverse momenta of the produced quarks. Experimentally, one has looked for this process in two-jet as well as inclusive particle production and has found a relatively low PT onset of hard scattering in {gamma}{gamma} interactions. This report examines the issue in more detail (high statistics) for charged particle inclusive production and checks if the heavier flavors display a similar behavior in inclusive K{sup 0} production.

Published
1993
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2. Search for elastic nondiagonal lepton-pair production ine+e−annihilation at √s=29 GeV

Author

J. J. Gomez-Cadenas, C. A. Heusch, G. Abrams, C. E. Adolphsen, C. Akerlof, J. P. Alexander, M. Alvarez, D. Amidei, A. R. Baden, J. Ballam, B. C. Barish, T. Barklow, B. A. Barnett, J. Bartelt, D. Blockus, G. Bonvicini, A. Boyarski, J. Boyer, B. Brabson, A. Breakstone, J. M. Brom, F. Bulos, P. R. Burchat, D. L. Burke, F. Butler, F. Calvino, R. J. Cence, J. Chapman, D. Cords, D. P. Coupal, H. C. DeStaebler, D. E. Dorfan, J. M. Dorfan, P. S. Drell, G. J. Feldman, E. Fernandez, R. C. Field, W. T. Ford, C. Fordham, R. Frey, D. Fujino, K. K. Gan, G. Gidal, L. Gladney, T. Glanzman, M. S. Gold, G. Goldhaber, L. Golding, A. Green, P. Grosse-Wiesmann, J. Haggerty, G. Hanson, R. Harr, F. A. Harris, C. M. Hawkes, K. Hayes, D. Herrup, T. Himel, M. Hoenk, R. J. Hollebeek, D. Hutchinson, J. Hylen, W. R. Innes, M. Jaffre, J. A. Jaros, I. Juricic, J. A. Kadyk, D. Karlen, J. Kent, S. R. Klein, A. Koide, W. Koska, W. Kozanecki, A. J. Lankford, R. R. Larsen, B. W. LeClaire, M. E. Levi, Z. Li, A. M. Litke, N. S. Lockyer, V. Lüth, C. Matteuzzi, J. A. J. Matthews, D. I. Meyer, B. D. Milliken, K. C. Moffeit, L. Müller, J. Nash, M. E. Nelson, D. Nitz, H. Ogren, R. A. Ong, K. F. O’Shaughnessy, S. I. Parker, C. Peck, A. Petersen, M. Petradza, F. C. Porter, P. Rankin, B. Richter, K. Riles, P. C. Rowson, D. R. Rust, H. F. W. Sadrozinski, T. Schaad, T. L. Schalk, H. Schellman, W. B. Schmidke, A. S. Schwarz, A. Seiden, P. D. Sheldon, J. G. Smith, A. Snyder, E. Soderstrom, D. P. Stoker, R. Stroynowski, R. Thun, G. H. Trilling, R. Tschirhart, C. de la Vaissiere, R. Van Kooten, H. Veltman, P. Voruganti, S. R. Wagner, P. Weber, A. J. Weinstein, A. J. Weir, S. Weisz, S. L. White, E. Wicklund, D. R. Wood, D. Y. Wu, and J. M. Yelton

Subjects
Physics, Particle physics, Annihilation, Electron–positron annihilation, High Energy Physics::Phenomenology, General Physics and Astronomy, Elementary particle, Fermion, Nuclear physics, Pair production, High Energy Physics::Experiment, Production (computer science), Storage ring, Lepton
Abstract

We have searched for the annihilation of e+e- into the exclusive channels e and at s =29 GeV, using 226 and 133 pb-1, respectively, of data taken with the Mark II detector at the SLAC storage ring PEP. The resulting candidate sample is compatible with the expected background from pair production. Our analysis yields 95%-C.L. cross-section limits of e/

Published
1991
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3. Test of QED to fourth order by study of four-lepton final states ine+e−interactions at 29 GeV with the Mark II detector

Author

M. Petradza, R. Thun, G. Abrams, D. Amidei, A. R. Baden, T. Barklow, A. Boyarski, J. Boyer, P. R. Burchat, D. L. Burke, F. Butler, J. M. Dorfan, G. J. Feldman, G. Gidal, L. Gladney, M. S. Gold, G. Goldhaber, J. Haggerty, G. Hanson, K. Hayes, D. Herrup, T. Himel, R. J. Hollebeek, W. R. Innes, J. A. Jaros, J. A. Kadyk, D. Karlen, S. R. Klein, A. J. Lankford, R. R. Larsen, B. W. LeClaire, M. E. Levi, N. S. Lockyer, V. Lüth, M. E. Nelson, R. A. Ong, M. L. Perl, B. Richter, K. Riles, P. C. Rowson, T. Schaad, H. Schellman, W. B. Schmidke, P. D. Sheldon, G. H. Trilling, D. R. Wood, and J. M. Yelton

Subjects
Coupling constant, Physics, Particle physics, Fourth order, Annihilation, Muon, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Elementary particle, Fermion, Lepton
Abstract

We have tested QED to fourth order in the coupling constant {alpha} in the large-{ital Q}{sup 2} region by studying four-lepton final states in {ital e}{sup +}{ital e}{sup {minus}} interactions with the Mark II detector at the SLAC storage ring PEP ({radical}{ital s} =29 GeV). All four final-state particles were detected at large angles with respect to the beam axis. For an integrated luminosity of 205 pb{sup {minus}1}, we observed ten {ital e}{sup +}{ital e}{sup {minus}}{ital e+}{ital e}{sup {minus}}, ten {ital e}{sup +}{ital e}{sup {minus}}{mu}{sup +}{mu}{sup {minus}}, and one {mu}{sup +}{mu}{sup {minus}}{mu}{sup +}{mu}{sup {minus}} events with opposite-charge pair masses greater than 1 GeV/{ital c}{sup 2}. These events show good agreement with the complete {alpha}{sup 4} QED calculation.

Published
1990
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4. Search for a nearly degenerate lepton doublet (L−,L0)

Author

W. B. Schmidke, D. Karlen, J. Dorfan, G. Hanson, A. J. Lankford, A. M. Boyarski, Michael Levi, J. A. Kadyk, H. Schellman, Patricia R. Burchat, J. A. Jaros, N. S. Lockyer, Timothy Barklow, I. Juricic, Mark E. Nelson, L. Golding, R. A. Ong, S. R. Klein, Burton Richter, J. Boyer, R. J. Hollebeek, G. J. Feldman, P. C. Rowson, B. W. Leclaire, G. S. Abrams, D. Herrup, D. L. Burke, R. R. Larsen, P. D. Sheldon, L. Gladney, T. Schaad, Gerson Goldhaber, J. M. Yelton, D. Amidei, A. R. Baden, F. Butler, K. Riles, V. Luth, George Gidal, M. L. Perl, Walter R. Innes, Kenneth G. Hayes, Darien Wood, G. H. Trilling, J. Haggerty, and M. S. Gold

Subjects
Physics, Particle physics, Annihilation, Branching fraction, Computer Science::Information Retrieval, High Energy Physics::Phenomenology, Order (ring theory), Elementary particle, Nuclear physics, Massless particle, High Energy Physics::Experiment, Neutrino, Energy (signal processing), Lepton
Abstract

We have searched for a heavy charged lepton with an associated neutrino of nearly the same mass in {ital e}{sup +}{ital e}{sup {minus}} annihilation data taken with the Mark II detector at a center-of-mass energy of 29 GeV. In order to suppress contamination from conventional two-photon reactions, this analysis uses a novel, radiative-tagging technique. Requiring the presence of an isolated, energetic photon allows a search for lepton doublets with mass splittings smaller than that previously accessible to experiment. No evidence for such a new lepton doublet has been found, enabling limits to be placed on allowed mass combinations. Mass splittings as low as 250--400 MeV/{ital c}{sup 2} are excluded for charged-lepton masses between 500 MeV/{ital c}{sup 2} and 10 GeV/{ital c}{sup 2}.

Published
1990
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5. A reanalysis of B0-B̄0 mixing in e+e− annihilation at 29 GeV

Author

A. Petersen, J. M. Brom, A. Seiden, P. Voruganti, F. Butler, D. Hutchinson, Darien Wood, K. O'Shaughnessy, H. O. Ogren, J. A. Jaros, A. S. Schwarz, M. L. Perl, C. W. Peck, W. Koska, Kenneth G. Hayes, J. Boyer, K. Riles, G. Bonvicini, J. A. Kadyk, A. Breakstone, R. P. Thun, D.P. Coupal, Stephen Robert Wagner, E. Soderstrom, R. R. Larsen, Ryszard Stroynowski, D. Fujino, J. Hylef, M. S. Gold, G. H. Trilling, D. Nitz, Gerson Goldhaber, W. R. Innes, F. C. Porter, D. Y. Wu, P. Rankin, D. Amidei, R. Frey, B. D. Milliken, Timothy Barklow, E. Wicklund, P. C. Rowson, B. W. Leclaire, S. R. Klein, G. Hanson, A. J. Lankford, J. Haggerty, Jordan Nash, S. L. White, J. G. Smith, H. F.W. Sadrozinski, Alan Litke, Cords D, T. Schalk, W. B. Schmidke, S. Weisz, B. B. Brabson, Michael Levi, R. J. Hollebeek, F. Calviño, P. Weber, Patricia R. Burchat, D. E. Dorfan, M. Petradza, R. A. Ong, H. Veltman, B. A. Barnett, D. P. Stoker, W. Kozanecki, H. Schellman, G. S. Abrams, M. Jaffre, F. A. Harris, K. K. Gan, E. Fernandez, C.M. Hawkes, R. Tschirhart, Sherwood Parker, G. J. Feldman, George Gidal, R. C. Field, I. Bartelt, Fordham C, K.C. Moffeit, D. Herrup, A. J. Weinstein, T. Glanzman, J. A. J. Matthews, V. Luth, A. Snyder, P.S. Drell, W. T. Ford, L. Gladney, DeStaebler Hc, N. S. Lockyer, Mark E. Nelson, I. Juricic, R. J. Cence, B. C. Barish, D. Karlen, L. Müller, D. I. Meyer, J. M. Yelton, A. R. Baden, T. Himel, J. Kent, P. D. Sheldon, D. R. Rust, Burton Richter, D. Blockus, J. Dorfan, A. M. Boyarski, A. J. Weir, R. Van Kooten, James P. Alexander, A. Green, D. L. Burke, T. Schaad, M. Alvarez, Grosse-Wiesmann P, R. Harr, J. W. Chapman, Adolphsen Ce, C. A. Heusch, and F. Bulos

Subjects
Quark, Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, High Energy Physics::Phenomenology, Hadron, Astrophysics::Cosmology and Extragalactic Astrophysics, Measure (mathematics), Nuclear physics, High Energy Physics::Experiment, Mixing (physics), Storage ring, Lepton
Abstract

Data taken by the Mark II detector at the PEP storage ring was used to measure the rate of dilepton production in multihadronic events produced by e + e − annihilation at √ s =29 GeV. We determine the probability that a hadron initially containing a b (b) quark decays to a positive (negative) lepton to be 0.17 −0.08 +0.15 , with 90% confidence level limits of 0.06 and 0.38.

Published
1990
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6. Radiativeτproduction and decay

Author

D. Y. Wu, K. Hayes, M. L. Perl, T. Barklow, A. Boyarski, P. R. Burchat, D. L. Burke, J. M. Dorfan, G. J. Feldman, L. Gladney, G. Hanson, R. J. Hollebeek, W. R. Innes, J. A. Jaros, D. Karlen, S. R. Klein, A. J. Lankford, R. R. Larsen, B. W. LeClaire, N. S. Lockyer, V. Lüth, R. A. Ong, B. Richter, K. Riles, J. M. Yelton, G. Abrams, D. Amidei, A. R. Baden, J. Boyer, F. Butler, G. Gidal, M. S. Gold, G. Goldhaber, L. Golding, J. Haggerty, D. Herrup, I. Juricic, J. A. Kadyk, M. E. Levi, M. E. Nelson, P. C. Rowson, H. Schellman, W. B. Schmidke, P. D. Sheldon, G. H. Trilling, D. R. Wood, and T. Schaad

Subjects
Nuclear physics, Physics, Antiparticle, Muon, Annihilation, Branching fraction, Electron–positron annihilation, Bremsstrahlung, Radiative transfer, High Energy Physics::Experiment, Lepton
Abstract

A study of the muon decay channel of the τ lepton with the presence of a photon has been carried out to verify theoretical predictions for the production rate of e + e - → τ + τ - γ and for the branching ratio of τ - → ν τ µ - ν µ γ. Included in this study is the first direct measurement of radiative tau decay. Using e + e - annihilation data taken at 29 GeV center-of-mass energy with the Mark II detector, we find the ratio of the measured τ - → ν τ µ - ν µ γ branching fraction to the expected value from QED to be 1.03 ± 0.42. The ratio of measured-to-predicted number of events from radiative T production, e + e - → τ + τ - γ, where one of the τ's decay to μνν is found to be 0.91 ± 0.20. We have not seen an indication of anomalous behavior in radiative tau events.

Published
1990
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7. Measurement ofK*andK0inclusive rates ine+e−annihilation at 29 GeV

Author

P. C. Rowson, J. M. Yelton, B. W. Leclaire, C. Zaiser, D. Amidei, A. R. Baden, W. R. Innes, D. Schlatter, C. Matteuzzi, G. Hanson, D. Herrup, J. B. Dillon, G. J. Feldman, R. R. Larsen, I. Juricic, L. Golding, R. A. Ong, Gerson Goldhaber, N. S. Lockyer, J. Dorfan, J. A. Jaros, A. M. Boyarski, G. S. Abrams, Michael Levi, M. L. Perl, Timothy Barklow, W. B. Schmidke, H. Schellman, D. L. Burke, M. S. Gold, T. Schaad, Kenneth G. Hayes, C. De La Vaissiere, P. D. Sheldon, Martin Breidenbach, A. J. Lankford, Burton Richter, Mark E. Nelson, V. Luth, T. Himel, Marc Ross, R. J. Hollebeek, F. Butler, George Gidal, K. Riles, D. Karlen, J. A. Kadyk, Darien Wood, J. Boyer, L. Gladney, J. Haggerty, P. R. Burchat, and G. H. Trilling

Subjects
Momentum, Physics, Nuclear physics, Particle physics, Annihilation, Meson, Electron–positron annihilation, Hadron, Elementary particle, Particle identification, Boson
Abstract

We have measured the K/sup 0/+K /sup 0/ inclusive cross section in e/sup +/e/sup -/ annihilation at 29 GeV with the Mark II detector SLAC PEP. We find 1.27 +- 0.03 +- 0.15 K/sup 0/+K /sup 0/ per hadronic event. We have also used time-of-flight particle identification to measure the K/sup + -/ rate over the momentum range 300--900 MeV/c.

Published
1985
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8. Inclusive Lepton Production ine+e−Annihilation at 29 GeV

Author

K. Hayes, P. D. Sheldon, A. Petersen, G. H. Trilling, P. C. Rowson, D. L. Burke, B. W. Leclaire, A. J. Weir, M. L. Perl, R. J. Hollebeek, W. B. Schmidke, Andrew Lankford, Patricia R. Burchat, J. M. Dorfan, N. S. Lockyer, L. Golding, M. S. Gold, K. Riles, J. Boyer, T. Schaad, F. Butler, L. Gladney, S. R. Klein, R. R. Larsen, R. A. Ong, D. Herrup, Mark E. Nelson, G. Gidal, Gordon H. Hanson, G. J. Feldman, Burton Richter, W. R. Innes, D. Amidei, H. Schellman, A. M. Boyarski, I. Juricic, J. A. Jaros, J. A. Kadyk, A. Baden, T. Barklow, Michael Levi, V. Lüth, John Yelton, J. S. Haggerty, Darien Wood, G. S. Abrams, D. Karlen, and G. Goldhaber

Subjects
Physics, Semileptonic decay, Particle physics, Annihilation, Muon, Branching fraction, High Energy Physics::Phenomenology, General Physics and Astronomy, Massless particle, Nuclear physics, Particle decay, Pair production, High Energy Physics::Experiment, Nuclear Experiment, Lepton
Abstract

We use data taken by the Mark II detector at the SLAC storage ring PEP to study inclusive lepton production in e+e- annihilation at 29 GeV. From fits to the inclusive lepton momentum and transverse-momentum spectra we measure the semileptonic branching ratios for charm and bottom hadrons. We also determine with good precision the mean value of the bottom fragmentation function using both electron and muon samples. © 1988 The American Physical Society.

Published
1988
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9. Study of noncollinear two-charged-particle events produced in 29-GeV electron-positron annihilation

Author

D. Herrup, G. S. Abrams, J. M. Yelton, L. Müller, D. Amidei, A. R. Baden, P. C. Rowson, B. W. Leclaire, C. Zaiser, J. A. Kadyk, Martin Breidenbach, Burton Richter, M. K. Gold, Gerson Goldhaber, D. Schlatter, J. Dorfan, C. Matteuzzi, D. Karlen, Kenneth G. Hayes, A. M. Boyarski, R. R. Larsen, N. S. Lockyer, R. J. Hollebeek, R. A. Ong, L. Golding, W. B. Schmidke, G. Hanson, C. De La Vaissiere, D. L. Burke, V. Luth, T. Schaad, Michael Levi, P. D. Sheldon, J. A. Jaros, Marc Ross, Mark E. Nelson, Timothy Barklow, H. Schellman, Darien Wood, G. J. Feldman, I. Juricic, F. Butler, J. Haggerty, M. L. Perl, Walter R. Innes, K. Riles, George Gidal, J. Boyer, A. J. Lankford, Patricia R. Burchat, and L. Gladney

Subjects
Nuclear physics, Massless particle, Physics, Annihilation, Muon, Pair production, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Electron–positron annihilation, Elementary particle, Atomic physics, Charged particle, Lepton
Abstract

This paper presents a study of events produced in 29-GeV electron-positron annihilation in which there are just two noncollinear charged particles, no detected photons, and two or more undetected particles. These events can be explained by attributing them primarily to the reactions e/sup +/e/sup -/..-->..e/sup +/e/sup -/e/sup +/e/sup -/ and e/sup +/e/sup -/..-->..e/sup +/e/sup -/..mu../sup +/..mu../sup -/ where just two particles appear in the Mark II detector. There is no evidence for unconventional sources for such events.

Published
1986
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10. D*+Production ine+e−Annihilation at 29 GeV

Author

C. Matteuzzi, Andrew Lankford, H. Schellman, G. J. Feldman, M. Franklin, C. A. Blocker, G. Zhao, J. M. Weiss, A. Roussarie, G. H. Trilling, A. D. Johnson, Martin Breidenbach, J. L. Siegrist, Gordon H. Hanson, Michael Levi, A. M. Boyarski, V. Lüth, A. Blondel, M. L. Perl, C. Zaiser, R. J. Hollebeek, Roy F Schwitters, G. Gidal, D. Schlatter, L. Golding, G. S. Abrams, Mark E. Nelson, Adam S. Backer, J. B. Dillon, D. Amidei, J. M. Yelton, B. W. Leclaire, L. Gladney, M. W. Eaton, J. F. Patrick, N. S. Lockyer, M. Werlen, G. von Dardel, J. A. Jaros, J. A. Kadyk, W. E. Dieterle, W. R. Innes, Burton Richter, D. L. Burke, J. M. Dorfan, T. Schaad, G. Goldhaber, J. Dorenbosch, R. R. Larsen, R. A. Vidal, J. Strait, B. Löhr, W. Chinowsky, and Yihua Wang

Subjects
Quark, Physics, Particle physics, Annihilation, Meson, High Energy Physics::Lattice, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, General Physics and Astronomy, Parton, Elementary particle, Nuclear physics, Fragmentation function, High Energy Physics::Experiment, Nuclear Experiment, Boson
Abstract

The production of the charmed meson state D*+ has been observed in e+e- annihilation at 29 GeV. The fragmentation function for charmed quarks appears to be peaked about z=0.5. © 1982 The American Physical Society.

Published
1982
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11. Λc+production and semileptonic decay in 29-GeVe+e−annihilation

Author

K. Riles, Michael Levi, A. Baden, T. Himel, J. Haggerty, T. Barklow, N. S. Lockyer, V. Lüth, R. R. Larsen, J. A. Kadyk, G. Gidal, Darien Wood, D. Herrup, G. H. Trilling, M. S. Gold, J. Boyer, Burton Richter, R. A. Ong, C. De La Vaissiere, Andrew Lankford, A. M. Boyarski, F. Butler, K. Hayes, J. A. Jaros, M. L. Perl, S. R. Klein, B. W. Leclaire, G. Goldhaber, Patricia R. Burchat, G. J. Feldman, I. Juricic, D. Amidei, P. D. Sheldon, W. R. Innes, D. Karlen, D. L. Burke, S. R. Wagner, G. S. Abrams, W. B. Schmidke, J. M. Dorfan, Gordon H. Hanson, T. Schaad, J. M. Yelton, H. Schellman, P. C. Rowson, R. J. Hollebeek, L. Gladney, and Mark E. Nelson

Subjects
Semileptonic decay, Charmed baryons, Nuclear physics, Physics, Particle decay, Particle physics, Annihilation, Muon, Branching fraction, Electron–positron annihilation, General Physics and Astronomy, Lambda baryon
Abstract

We present results on c+ production in 29-GeV e+e- annihilation. The c+ are observed via their semileptonic decays to e+X and +X. With radiative corrections, we find (e+e-c+X)Bc+eX)= 1.5±0.6±0.5 pb or 0.0038±0.0015±0.0012 c+e+X decay per hadronic event, and (e+e-c+X)B(c+X)= 1.4±1.4±0.4 pb or 0.0035±0.0035±0. 0011 c++X decay per hadronic event. These results can be used to place constraints on the predictions of various production models. © 1989 The American Physical Society.

Published
1989
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12. Measurement of theD0andD+lifetimes

Author

D. L. Burke, M. L. Perl, Walter R. Innes, D. Karlen, T. Schaad, G. S. Abrams, Kenneth G. Hayes, D. Herrup, W. B. Schmidke, L. Gladney, Burton Richter, Gerson Goldhaber, A. J. Lankford, M. Levi, J. Haggerty, Martin Breidenbach, Patricia R. Burchat, R. R. Larsen, J. Dorfan, Darien Wood, A. M. Boyarski, J. M. Yelton, D. Amidei, A. R. Baden, J. A. Jaros, P. C. Rowson, B. W. Leclaire, M. K. Gold, C. Zaiser, George Gidal, V. Luth, I. Juricic, P. D. Sheldon, J. Boyer, H. Schellman, C. De La Vaissiere, Timothy Barklow, Mark E. Nelson, F. Butler, K. Riles, L. Golding, Marc Ross, N. S. Lockyer, R. J. Hollebeek, G. J. Feldman, C. Matteuzzi, R. A. Ong, George H. Trilling, J. A. Kadyk, and G. Hanson

Subjects
Physics, Nuclear physics, Annihilation, Meson, Electron–positron annihilation, Hadron, Elementary particle, Atomic physics, Particle detector, Bhabha scattering, Boson
Abstract

We have used a high-resolution drift chamber in the Mark II detector at the SLAC e+e- storage ring PEP to measure the lifetimes of the D0 and D+ mesons produced in e+e- annihilations at 29 GeV. Based on a sample of 74 decays for the D0 mesons and 23 decays for the D+ mesons, the lifetimes are found to be &=(4.7-0.8+0.9) 0.5×10-13 sec and &=(8.9-2.7+3.8) 1.3×10-13 sec. This leads to a ratio of lifetimes &=1.9-0.7 0.3+0.9.. AE © 1986 The American Physical Society.

Published
1986
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13. Search for heavy-neutrino production ine+e−annihilation at 29 GeV

Author

A. Baden, L. Golding, T. Barklow, R. A. Ong, J. Boyer, P. C. Rowson, G. S. Abrams, D. Herrup, G. J. Feldman, K. Hayes, J. A. Jaros, J. Haggerty, P. D. Sheldon, L. Gladney, C. Matteuzzi, M. L. Perl, Wendt C, G. Gidal, Gordon H. Hanson, Andrew Lankford, G. H. Trilling, Mark E. Nelson, G. Goldhaber, M. S. Gold, R. J. Hollebeek, de la Vaissiere C, N. S. Lockyer, Michael Levi, F. Butler, Lüth, J. M. Yelton, H. Schellman, Klein, W. R. Innes, Burton Richter, D. Amidei, D. L. Burke, Patricia R. Burchat, A. M. Boyarski, R. R. Larsen, W. B. Schmidke, J. M. Dorfan, T. Schaad, B. W. Leclaire, K. Riles, Juricic I I, J. A. Kadyk, Darien Wood, and D. Karlen

Subjects
Physics, Nuclear physics, Range (particle radiation), Particle physics, Annihilation, Neutral current, Electron–positron annihilation, General Physics and Astronomy, High Energy Physics::Experiment, Weak current, Heavy neutrino, Neutrino, Storage ring
Abstract

We report a search for long-lived heavy neutrinos produced by the neutral weak current in e+e- annihilation at 29 GeV at the SLAC storage ring PEP. Data from the Mark II detector are examined for evidence of events with one or more separated vertices in the radial range of 2 mm to 10 cm. No events were found that were consistent with the search hypothesis, ruling out heavy neutrinos with mean decay lengths of 1 to 20 cm in the mass range 1 to 13 GeV/c2. © 1987 The American Physical Society.

Published
1987
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14. Precise Measurement ofτ-Decay Charged-Particle Multiplicity Distribution

Author

M. L. Perl, N. S. Lockyer, M. Franklin, A. D. Johnson, Martin Breidenbach, C. A. Blocker, H. Schellman, W. E. Dieterle, G. J. Feldman, L. Golding, Larry D. Gladney, A. M. Boyarski, J. B. Dillon, D. Amidei, R. R. Larsen, C. Zaiser, Walter R. Innes, R. A. Vidal, B. Löhr, R. J. Hollebeek, D. Schlatter, W. Chinowsky, G. Zhao, Yihua Wang, V. Lüth, C. Matteuzzi, D. L. Burke, J. L. Siegrist, J. Strait, A. Bäcker, J. M. Yelton, G. H. Trilling, A. Blondel, Michael Levi, J. M. Dorfan, Roy F Schwitters, T. Schaad, M. W. Eaton, B. W. Leclaire, A. Roussarie, M. Werlen, J. A. Kadyk, G. von Dardel, G. Goldhaber, J. A. Jaros, Burton Richter, G. S. Abrams, J. F. Patrick, J. Dorenbosch, Andrew Lankford, Gordon H. Hanson, Mark E. Nelson, J. M. Weiss, and G. Gidal

Subjects
Physics, Nuclear physics, Annihilation, Pair production, Branching fraction, General Physics and Astronomy, Multiplicity (mathematics), Elementary particle, Charged particle, Storage ring, Lepton
Abstract

The charged-particle multiplicity distribution in decays is determined from data collected at the e+e- storage ring PEP. The one-, three-, and five-charged-particle inclusive branching fractions are (86 ± 2)%, (14 ± 2)%, and < 0.5%, respectively. © 1982 The American Physical Society.

Published
1982
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15. Charged-meson pair production ingammaγinteractions

Author

J. Boyer, D. L. Burke, F. Butler, G. Gidal, G. S. Abrams, D. Amidei, A. R. Baden, T. Barklow, A. M. Boyarski, M. Breidenbach, P. Burchat, J. M. Dorfan, G. J. Feldman, L. Gladney, M. S. Gold, G. Goldhaber, L. J. Golding, J. Haggerty, G. Hanson, K. Hayes, D. Herrup, R. J. Hollebeek, W. R. Innes, J. A. Jaros, I. Juricic, J. A. Kadyk, D. Karlen, S. R. Klein, A. J. Lankford, R. R. Larsen, B. W. LeClaire, M. E. Levi, N. S. Lockyer, V. Lüth, C. Matteuzzi, M. E. Nelson, R. A. Ong, M. L. Perl, B. Richter, K. Riles, M. C. Ross, P. C. Rowson, T. Schaad, H. Schellman, W. B. Schmidke, P. D. Sheldon, J. R. Smith, G. H. Trilling, C. de la Vaissiere, D. R. Wood, J. M. Yelton, and C. Zaiser

Subjects
Nuclear physics, Physics, Quantum chromodynamics, Particle physics, Pair production, Annihilation, Pion, Meson, Hadron, General Physics and Astronomy, Elementary particle, Charged particle
Abstract

The cross section for the production of ..pi../sup +/..pi../sup -/ or K/sup +/K/sup -/ pairs in ..gamma gamma.. interactions is measured for m/sub pipi/ between 1.7 and 3.5 GeV/c/sup 2/ and for two intervals of ..gamma gamma.. center-of-mass scattering angle. Results are compared with predictions of a QCD model.

Published
1986
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16. Measurement of Energy Correlations ine+e−→Hadrons

Author

B. W. Leclaire, Burton Richter, M. W. Coles, R. R. Larsen, D. L. Burke, J. M. Dorfan, G. von Dardel, T. Schaad, G. Goldhaber, J. Dorenbosch, J. A. Jaros, M. L. Perl, W. E. Dieterle, R. J. Hollebeek, G. H. Trilling, N. S. Lockyer, Adam S. Backer, Gordon H. Hanson, G. Zhao, D. Schlatter, Andrew Lankford, J. L. Siegrist, Larry D. Gladney, C. A. Blocker, V. Lüth, G. J. Feldman, Walter R. Innes, L. Golding, A. Roussarie, D. L. Scharre, J. M. Yelton, G. S. Abrams, R. A. Vidal, M. W. Eaton, A. D. Johnson, Martin Breidenbach, J. B. Dillon, C. Zaiser, D. Amidei, I. Videau, J. Strait, M. Werlen, B. Löhr, Mark E. Nelson, J. F. Patrick, M. Franklin, A. Blondel, J. M. Weiss, J. A. Kadyk, G. Gidal, A. M. Boyarski, Michael Levi, Roy F Schwitters, C. Matteuzzi, W. Chinowsky, Yihua Wang, and H. Schellman

Subjects
Quantum chromodynamics, Physics, Coupling constant, Particle physics, Annihilation, Detector, Hadron, General Physics and Astronomy, Elementary particle, Linear particle accelerator, Nuclear physics, Physics::Accelerator Physics, High Energy Physics::Experiment, Storage ring
Abstract

Energy correlations have been measured with the MARK II detector at the PEP storage ring (Stanford Linear Accelerator Center) at c.m. energy of 29 GeV and are compared to first-order QCD predictions. Fragmentation processes are significant and limit the precision with which the first-order strong-coupling constant can be determined. © 1982 The American Physical Society.

Published
1982
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17. Observation ofΞ−production ine+e−annihilation at 29 GeV

Author

J. A. Kadyk, Kenneth G. Hayes, V. Luth, A. Baden, T. Himel, R. J. Hollebeek, P. C. Rowson, J. Boyer, D. Amidei, G. G. Hanson, G. H. Trilling, H. Schellman, J. S. Haggerty, Darien Wood, F. Butler, I. Juricic, John Yelton, D. L. Burke, R. R. Larsen, George Gidal, L. Gladney, W. B. Schmidke, M. S. Gold, G. J. Feldman, L. Golding, C. Matteuzzi, K. Riles, B. W. Leclaire, Mark E. Nelson, T. Schaad, R. A. Ong, M. L. Perl, J. A. Jaros, G. S. Abrams, W. R. Innes, D. Herrup, J. Dorfan, M. E. Levi, G. Goldhaber, N. S. Lockyer, A. M. Boyarski, Patricia R. Burchat, S. R. Klein, C. De La Vaissiere, P. D. Sheldon, A. J. Lankford, And C. Zaiser, A. Petersen, D. Karlen, Timothy Barklow, and Burton Richter

Subjects
Physics, Combinatorics, Particle physics, Annihilation, Electron–positron annihilation, General Physics and Astronomy, Production (computer science), Production rate
Abstract

Author(s): Klein, SR; Himel, TM; Abrams, G; Amidei, D; Baden, AR; Barklow, T; Boyarski, AM; Boyer, J; Burchat, PR; Burke, DL; Butler, F; Dorfan, JM; Feldman, GJ; Gidal, G; Gladney, L; Gold, MS; Goldhaber, G; Golding, L; Haggerty, J; Hanson, G; Hayes, K; Herrup, D; Hollebeek, RJ; Innes, WR; Jaros, JA; Juricic, I; Kadyk, JA; Karlen, D; Lankford, AJ; Larsen, RR; LeClaire, BW; Levi, M; Lockyer, NS; Luth, V; Matteuzzi, C; Nelson, ME; Ong, RA; Perl, ML; Petersen, A; Richter, B; Riles, K; Rowson, PC; Schaad, T; Schellman, H; Schmidke, WB; Sheldon, PD; Trilling, GH; de la Vaissiere C; Wood, DR; Yelton, JM; Zaiser, AC | Abstract: Inclusive - production in e+e- annihilation at 29 GeV has been measured with the Mark II detector. From an integrated luminosity of 207 pb-1, we determine a production rate of 0.0170.0040.004 -++ per hadronic event. A search for *0(1530)-+ leads to an upper limit of N(*0)/N(-)l0.35 at a 90% confidence level. © 1987 The American Physical Society.

Published
1987
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18. Bose-Einstein correlations ine+e−collisions

Author

I. Juricic, G. Goldhaber, G. Gidal, G. Abrams, D. Amidei, A. R. Baden, J. Boyer, F. Butler, W. C. Carithers, M. S. Gold, L. Golding, J. Haggerty, D. Herrup, J. A. Kadyk, M. E. Levi, M. E. Nelson, P. C. Rowson, H. Schellman, W. B. Schmidke, P. D. Sheldon, G. H. Trilling, D. R. Wood, T. Barklow, A. Boyarski, M. Breidenbach, P. Burchat, D. L. Burke, D. Cords, J. M. Dorfan, G. J. Feldman, L. Gladney, G. Hanson, K. Hayes, D. G. Hitlin, R. J. Hollebeek, W. R. Innes, J. A. Jaros, D. Karlen, S. R. Klein, A. J. Lankford, R. R. Larsen, B. W. LeClaire, N. S. Lockyer, V. Lüth, R. A. Ong, M. L. Perl, B. Richter, K. Riles, M. C. Ross, R. H. Schindler, J. M. Yelton, T. Schaad, and R. F. Schwitters

Subjects
Nuclear physics, Quantum chromodynamics, Physics, Particle physics, Pion, Pair production, Annihilation, Meson, Hadron, High Energy Physics::Experiment, Elementary particle, Quarkonium
Abstract

The MARK II detector is used to study the Bose-Einstein correlation between pairs and triplets of charged pions produced in hadronic decays of the J)psi), the ..sqrt..s = 4 to 7 GeV continuum above the J)psi), two photon events at ..sqrt..s = 29 GeV, and e/sup )plus/)e/sup )minus/) annihilation events at ..sqrt..s = 29 GeV as a function of Q/sup 2/, the four-momentum transfer squared. After corrections for Coulomb effects and pion misidentification, we find a nearly full Bose-Einstein enhancement ..cap alpha.. in the J)psi) and the two photon data and about half the maximum value in the other two data sets. The radius parameter )tau)(an average over space and time) given by pion pair analyses lies within a band of +-0.10 fm around 0.73 fm and is the same, within errors, for all four data sets. Pion triplet analyses also give a consistent radius of approx. 0.54 fm. fits to two-dimensional distributions R(q/sub T//sup 2/, q/sub C//sup 2/) of invariant components of Q/sup 2/ = q/sub T//sup 2/ )plus) q/sub C//sup 2/ give )tau)/sub T/ approx. )tau)C approx. )tau), where q/sub T/ is the transverse three-momentum difference calculated with respect to the net pair three-momentum, and q/sub C/ ismore » in effect the longitudinal three-momentum difference in the pion pair rest frame. When q/sub T/ is calculated with respect to the jet axis for two-jet events in the e/sup )plus/)e/sup )minus/) annihilation data at ..sqrt..s = 29 GeV, a fit to R(q/sub T//sup 2/, q/sub C//sup 2/) also gives )tau)/sub T/ approx. )tau)/sub C/ approx. )tau). Noting that q/sub L/ and q/sub 0/ are not invariant, we make fits to R(/sub T//sup T/, q/sub L//sup 2/) and to R(q/sub T//sup 2/, q/sub 0//sup 2/) (Kopylov formulation), and we find )tau)/sub 0/ approx. )tau)/sub L/ approx. )23))tau)/sub T/ to )12))tau)/sub T/. 44 refs., 43 figs., 15 tabs« less

Published
1989
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19. Determination ofαsfrom energy-energy correlations ine+e−annihilation at 29 GeV

Author

J. S. Haggerty, C. A. Heusch, R. Van Kooten, W. Koska, Darien Wood, B. A. Barnett, L. Golding, R. Tschirhart, Kenneth G. Hayes, A. J. Lankford, J. A. Kadyk, D.P. Coupal, Stephen Robert Wagner, S. L. White, Timothy Barklow, P. S. Drell, D. L. Burke, R. Harr, H. O. Ogren, J. A. Jaros, F. Calviño, A. S. Schwarz, Ryszard Stroynowski, M. Petradza, R. A. Ong, D. Fujino, G. Bonvicini, J. P. Alexander, M. L. Perl, I. Juricic, DeStaebler Hc, B. C. Barish, A. Green, R. R. Larsen, P. Rankin, Alan Litke, R. J. Hollebeek, G. S. Abrams, H. F.W. Sadrozinski, A. Snyder, J. M. Brom, J. W. Chapman, D. Karlen, W. B. Schmidke, T. Schalk, G. J. Feldman, R. Frey, D. Nitz, D. Y. Wu, D. Amidei, T. Schaad, R. P. Thun, D. Hutchinson, W. T. Ford, J. Hylen, Gerson Goldhaber, H. Schellman, M. Alvarez, L. Müller, E. Fernandez, B. B. Brabson, Adolphsen Ce, J. A. J. Matthews, W. Kozanecki, Mark E. Nelson, P. R. Burchat, J. Kent, Z. Li, B. D. Milliken, D. I. Meyer, Grosse-Wiesmann P, A. Petersen, E. Wicklund, K. K. Gan, P. C. Rowson, B. W. Leclaire, J. G. Smith, F. A. Harris, D. R. Rust, A. Koide, P. Weber, John E. Bartelt, D. Herrup, A. Seiden, F. Butler, K. Riles, D. P. Stoker, M. E. Levi, P. Voruganti, T. Glanzman, R. C. Field, K.C. Moffeit, Jordan Nash, J. Boyer, W. R. Innes, M. Hoenk, F. Bulos, F. C. Porter, J. Ballam, M. Jaffré, Burton Richter, C. De La Vaissiere, D. Blockus, V. Luth, S. Weisz, R. J. Cence, George Gidal, Larry D. Gladney, P. D. Sheldon, Carl W. Akerlof, Cords D, A. J. Weinstein, Sherwood Parker, G. Hanson, C. Matteuzzi, A. Baden, K. O'Shaughnessy, C. W. Peck, J. Dorfan, John Yelton, A. M. Boyarski, S. R. Klein, C. M. Hawkes, G. H. Trilling, E. Soderstrom, N. S. Lockyer, A. J. Weir, T. Himel, Fordham C, A. Breakstone, D. E. Dorfan, M. S. Gold, and H. Veltman

Subjects
Quantum chromodynamics, Coupling constant, Nuclear physics, Physics, Particle physics, Annihilation, Electron–positron annihilation, Quark model, Hadron, High Energy Physics::Experiment, Nuclear Experiment, Storage ring, Hadronization
Abstract

We have studied the energy-energy correlation in e+e- annihilation into hadrons at s =29 GeV using the Mark II detector at the SLAC storage ring PEP. We find to O(s2) that s=0.1580.0030.008 if hadronization is described by string fragmentation. Independent fragmentation schemes give s=0.100.14, and give poor agreement with the data. A leading-log shower fragmentation model is found to describe the data well. © 1988 The American Physical Society.

Published
1988
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20. Observation ofΩ−Production ine+e−Annihilation at 29 GeV

Author

D. Amidei, H. Schellman, G. S. Abrams, I. Juricic, M. S. Gold, G. J. Feldman, Patricia R. Burchat, Burton Richter, G. Gidal, A. Petersen, J. A. Kadyk, Mark E. Nelson, R. R. Larsen, R. J. Hollebeek, L. Golding, R. A. Ong, D. Herrup, M. L. Perl, A. Baden, N. S. Lockyer, A. M. Boyarski, C. De La Vaissiere, T. Barklow, P. D. Sheldon, J. Haggerty, W. R. Innes, B. W. Leclaire, Michael Levi, V. Lüth, John Yelton, D. L. Burke, L. Gladney, G. Goldhaber, K. Hayes, F. Butler, W. B. Schmidke, J. M. Dorfan, G. H. Trilling, T. Schaad, Darien Wood, D. Karlen, C. Matteuzzi, Gordon H. Hanson, J. Boyer, J. A. Jaros, P. C. Rowson, T. Himel, Andrew Lankford, S. R. Klein, and K. Riles

Subjects
Physics, Particle physics, Annihilation, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Hyperon, General Physics and Astronomy, Omega baryon, Omega, Baryon, Nuclear physics, Diquark, High Energy Physics::Experiment, Nuclear Experiment
Abstract

Inclusive ..cap omega../sup -/ production in e/sup +/e/sup -/ annihilation at 29 GeV has been measured with the Mark II detector. From an integrated luminosity of 207 pb/sup -1/, we determine a production rate of 0.014 +- 0.006 +- 0.004 ..cap omega../sup -/,Omega-bar/sup +/ per hadronic event. This is roughly 35 times the Lund-model prediction of 0.0004 ..cap omega../sup -/,Omega-bar/sup +/ per hadronic event, but comparable to the Webber-model prediction of 0.006 ..cap omega../sup -/,Omega-bar/sup +/ per hadronic event. The large rate of ..cap omega../sup -/ production, compared with production rates for other baryons, and with theoretical predictions based on diquark models, indicates that spin suppression does not hold for ..cap omega../sup -/ production.

Published
1987
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21. Comparison of the particle flow in Three-Jet and radiative Two-Jet Events frome+e−Annihilation atEc.m.=29GeV

Author

R. J. Hollebeek, J. Haggerty, J. A. Kadyk, G. J. Feldman, P. C. Rowson, D. L. Burke, D. Amidei, M. C. Ross, P. R. Burchat, W. B. Schmidke, J. M. Dorfan, L. Golding, K. Riles, R. A. Ong, G. Goldhaber, T. Schaad, H. Schellman, D. Karlen, F. Butler, Andrew Lankford, B. W. Leclaire, J. Boyer, M. L. Perl, M. S. Gold, D. Herrup, A. Baden, T. Barklow, A. M. Boyarski, A. Petersen, W. R. Innes, J. A. Jaros, G. H. Trilling, C. Matteuzzi, N. S. Lockyer, P. D. Sheldon, R. R. Larsen, Juricic I I, Darien Wood, L. Gladney, G. Gidal, Zaiser aC, de la Vaissiere C, Mark E. Nelson, Burton Richter, Lüth, G. S. Abrams, Gordon H. Hanson, Michael Levi, John Yelton, and K. Hayes

Subjects
Quark, Physics, Jet (fluid), Particle physics, Annihilation, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, General Physics and Astronomy, Elementary particle, Gluon, Nuclear physics, Radiative transfer, High Energy Physics::Experiment, Event (particle physics)
Abstract

We have made a detailed comparison of the charged-particle flow in three-jet events (e+e-qq»g) and radiative two-jet events (e+e-qq») from e+e- annihilation at Ec.m.=29 GeV. Accurate comparisons can be made because these two event types have similar topologies. In the angular region between the quark and antiquark jets, we observe substantially fewer charged tracks in the two-jet events than in the radiative three-jet events. © 1986 The American Physical Society.

Published
1986
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22. Multihadronic events atEc.m.=29 GeV and predictions of QCD models fromEc.m.=29 GeV toEc.m.=93 GeV

Author

B. W. Leclaire, Cords D, John Yelton, Jordan Nash, C. A. Heusch, K. K. Gan, S. Weisz, L. Golding, K. O'Shaughnessy, W. Koska, C. W. Peck, T. Schalk, D. Herrup, E. Fernandez, A. J. Weir, R. J. Hollebeek, Kenneth G. Hayes, P. Voruganti, R. Harr, J. S. Haggerty, D. R. Rust, E. Soderstrom, R. C. Field, K.C. Moffeit, Sherwood Parker, E. Wicklund, Fordham C, Larry D. Gladney, A. Breakstone, R. Frey, C. De La Vaissiere, Darien Wood, B. A. Barnett, Adolphsen Ce, Timothy Barklow, Alan Litke, A. Koide, P. Weber, J. A. Jaros, A. J. Weinstein, John E. Bartelt, M. E. Levi, D.P. Coupal, J. W. Chapman, Stephen Robert Wagner, M. Petradza, R. A. Ong, C. M. Hawkes, A. Snyder, A. Petersen, J. A. J. Matthews, W. Kozanecki, H. O. Ogren, P. S. Drell, D. Amidei, T. Himel, R. R. Larsen, G. S. Abrams, B. B. Brabson, F. Bulos, Ryszard Stroynowski, D. Fujino, M. S. Gold, A. Green, W. T. Ford, A. Seiden, F. Butler, P. Rankin, N. S. Lockyer, DeStaebler Hc, A. S. Schwarz, G. Bonvicini, George Gidal, J. P. Alexander, Mark E. Nelson, F. Calviño, M. Jaffré, M. L. Perl, H. F.W. Sadrozinski, Gerson Goldhaber, I. Juricic, H. Schellman, H. Veltman, R. J. Cence, Z. Li, J. Boyer, Carl W. Akerlof, D. I. Meyer, B. D. Milliken, Grosse-Wiesmann P, F. A. Harris, T. Glanzman, R. Tschirhart, K. Riles, M. Hoenk, S. L. White, D. Nitz, D. Y. Wu, P. D. Sheldon, J. Ballam, J. Hylen, R. Van Kooten, P. R. Burchat, R. P. Thun, D. P. Stoker, A. J. Lankford, B. C. Barish, D. Karlen, J. Kent, Burton Richter, D. Blockus, J. Dorfan, A. M. Boyarski, S. R. Klein, L. Müller, G. J. Feldman, D. L. Burke, T. Schaad, M. Alvarez, W. R. Innes, F. C. Porter, J. A. Kadyk, W. B. Schmidke, G. Hanson, C. Matteuzzi, A. Baden, G. H. Trilling, J. M. Brom, D. Hutchinson, J. G. Smith, D. E. Dorfan, and P. C. Rowson

Subjects
Nuclear physics, Physics, Quantum chromodynamics, Particle physics, Annihilation, Electron–positron annihilation, Hadron, High Energy Physics::Experiment, Elementary particle, Parton, Rapidity, Hadronization
Abstract

Multihadronic e/sup +/e/sup -/ annihilation events at a center-of-mass energy of 29 GeV have been studied with both the original (PEP 5) Mark II and the upgraded Mark II detectors. Detector-corrected distributions from global shape analyses such as aplanarity, Q/sub 2/-Q/sub 1/, sphericity, thrust, minor value, oblateness, and jet masses, and inclusive charged-particle distributions including x, rapidity, p/sub perpendicular/, and particle flow are presented. These distributions are compared with predictions from various multihadron event models which use leading-logarithmic shower evolution or QCD matrix elements at the parton level and string or cluster fragmentation for hadronization. The new generation of parton-shower models gives, on the average, a better description of the data than the previous parton-shower models. The energy behavior of these models is compared to existing e/sup +/e/sup -/ data. The predictions of the models at a center-of-mass energy of 93 GeV, roughly the expected mass of the Z/sup 0/, are also presented.

Published
1988
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23. Inclusive Charged-Particle Distribution in Nearly Threefold-Symmetric Three-Jet Events atEc.m.=29GeV

Author

P. D. Sheldon, D. Karlen, J. Haggerty, R. R. Larsen, Martin L. Perl, D. L. Burke, G. J. Feldman, L. Golding, V. Lüth, W. B. Schmidke, C. Zaiser, J. M. Dorfan, John Yelton, T. Schaad, G. Goldhaber, A. Baden, Darien Wood, R. A. Ong, M. E. Levi, K. Hayes, Keith Riles, T. Barklow, Patricia R. Burchat, G. H. Trilling, Walter R. Innes, Larry D. Gladney, Burton Richter, M. C. Ross, S. R. Klein, Mark E. Nelson, C. De La Vaissiere, D. Amidei, A. M. Boyarski, F. Butler, G. Gidal, H. Schellman, R. J. Hollebeek, A. Petersen, I. Juricic, P. C. Rowson, D. Herrup, B. W. Leclaire, J. A. Kadyk, N. S. Lockyer, C. Matteuzzi, Gordon H. Hanson, J. Boyer, J. A. Jaros, Andrew Lankford, G. S. Abrams, and Martin Breidenbach

Subjects
Nuclear physics, Quark, Physics, Particle physics, Annihilation, Distribution (number theory), Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, General Physics and Astronomy, High Energy Physics::Experiment, Jet (particle physics), Charged particle, Gluon
Abstract

We report a measurement of the inclusive charged-particle distribution for gluon jets derived from nearly threefold-symmetric three-jet events taken at center-of-mass energy of 29 GeV in e+e- annihilation. The charged-particle spectrum for these jets is observed to fall off more rapidly than those of quark jets of the same energy. © 1985 The American Physical Society.

Published
1985
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24. Variation of the strong coupling constant from a measurement of the jet energy spread in e+e− annihilation

Author

R. R. Larsen, W. E. Dieterle, W. R. Innes, C. Zaiser, J. A. Kadyk, C. Matteuzzi, Mark E. Nelson, J. Strait, B. Löhr, J. B. Dillon, D. Amidei, M. W. Eaton, R. J. Hollebeek, Gordon H. Hanson, B. W. Leclaire, P. D. Sheldon, M. Franklin, P. C. Rowson, M. S. Gold, H. Schellman, M. L. Perl, A. D. Johnson, Martin Breidenbach, A. M. Boyarski, L. Gladney, D. L. Burke, G. J. Feldman, D. Schlatter, J. M. Dorfan, T. Schaad, Burton Richter, J. M. Yelton, C. De La Vaissiere, Michael Levi, V. Lüth, Roy F Schwitters, G. S. Abrams, G. Goldhaber, J. A. Jaros, J. F. Patrick, G. Gidal, Andrew Lankford, N. S. Lockyer, L. Golding, and C. A. Blocker

Subjects
Quantum chromodynamics, Momentum, Physics, Nuclear and High Energy Physics, Jet (fluid), Range (particle radiation), Annihilation, Quantum electrodynamics, Hadron, Momentum transfer, High Energy Physics::Experiment, Constant (mathematics)
Abstract

A measurement of jet energy spread in the reaction e+e− → hadrons is presented. Using a jet calculus model for the jet development we determine the variation of the strong coupling constant with respect to momentum transfer. The observed variation is consistent with that expected for QCD over a wide range of momentum transfers. This method alone is not sufficient to distinguish QCD from simple limited transverse momentum models.

Published
1983
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25. ηandη′Production ine+e−Annihilation at 29 GeV. Evidence for theDs±Decays intoηπ±andη′π±

Author

N. S. Lockyer, G. S. Abrams, R. R. Larsen, P. C. Rowson, M. S. Gold, D. Karlen, L. Golding, R. A. Ong, K. Riles, P. D. Sheldon, K. Hayes, G. J. Feldman, F. Butler, A. M. Boyarski, M. L. Perl, G. Goldhaber, Juricic I I, P. R. Burchat, Gordon H. Hanson, J. Boyer, Lüth, D. Herrup, A. Baden, G. Gidal, B. W. Leclaire, D. Amidei, J. A. Jaros, H. Schellman, G. H. Trilling, W. R. Innes, J. S. Haggerty, L. Gladney, J. A. Kadyk, T. Barklow, Mark E. Nelson, Darien Wood, Michael Levi, Burton Richter, R. J. Hollebeek, John Yelton, Klein, D. L. Burke, W. B. Schmidke, J. M. Dorfan, T. Schaad, G. Wormser, and Andrew Lankford

Subjects
Physics, Particle physics, Annihilation, Meson, Electron–positron annihilation, Hadron, General Physics and Astronomy, Elementary particle, Nuclear physics, Particle decay, Mass spectrum, High Energy Physics::Experiment, Nuclear Experiment, Boson
Abstract

eta production has been investigated by the Mark II Collaboration at the SLAC e/sup +/e/sup -/ storage ring PEP. eta particles are reconstructed by their ..gamma gamma.. decay mode. The eta fragmentation function has been measured and found to be in good agreement with the Lund-model prediction. eta' production has been measured for the first time in high-energy e/sup +/e/sup -/ annihilation. There is evidence at the 3sigma level for D/sub s//sup +- / decay into eta..pi../sup +/ and eta'..pi../sup +- /.

Published
1988
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26. Weak Neutral Currents ine+e−Collisions ats=29GeV

Author

A. M. Boyarski, P. C. Rowson, D. Schlatter, L. Gladney, L. Golding, W. R. Innes, J. A. Kadyk, R. R. Larsen, C. De La Vaissiere, R. A. Ong, G. Goldhaber, Martin Breidenbach, C. A. Blocker, M. L. Perl, R. J. Hollebeek, I. Juricic, M. Jonker, G. Gidal, H. Schellman, Burton Richter, B. W. Leclaire, Mark E. Nelson, A. Baden, P. D. Sheldon, D. Herrup, C. Matteuzzi, Gordon H. Hanson, N. S. Lockyer, J. M. Yelton, Michael Levi, V. Lüth, Patricia R. Burchat, Roy F Schwitters, C. Zaiser, G. H. Trilling, J. A. Jaros, D. L. Burke, J. M. Dorfan, Andrew Lankford, T. Schaad, James Strait, M. C. Ross, D. Amidei, G. J. Feldman, J. F. Patrick, M. S. Gold, and G. S. Abrams

Subjects
Physics, Nuclear physics, Particle physics, Annihilation, Pair production, Electron–positron annihilation, Electroweak interaction, General Physics and Astronomy, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Universality (dynamical systems), Lepton
Abstract

The differential cross sections for lepton pair production in e+e- annihilation at 29 GeV have been measured and found to be in good agreement with the standard model of the electroweak interaction. With the assumption of e-μ-τ universality, the weak neutral-current couplings are determined to be ga2=0.23±0.05 and gv2=0.03±0.04. © 1983 The American Physical Society.

Published
1983
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27. ΛProduction ine+e−Annihilation at 29 GeV

Author

C. de la Vaissiere, V. Luth, G. S. Abrams, D. Amidei, A. R. Baden, T. Barklow, A. M. Boyarski, J. Boyer, M. Breidenbach, P. Burchat, D. L. Burke, F. Butler, J. W. Dillon, J. M. Dorfan, G. J. Feldman, G. Gidal, L. Gladney, M. S. Gold, G. Goldhaber, L. G. Golding, G. Hanson, J. Haggerty, D. Herrup, T. Himel, R. J. Hollebeek, W. R. Innes, J. A. Jaros, I. Juricic, J. A. Kadyk, S. R. Klein, A. J. Lankford, R. R. Larsen, B. W. LeClaire, M. E. Levi, N. S. Lockyer, C. Matteuzzi, M. E. Nelson, R. A. Ong, M. L. Perl, B. Richter, M. C. Ross, P. C. Rowson, T. Schaad, H. Schellman, W. B. Schmidke, P. D. Sheldon, G. H. Trilling, J. M. Yelton, D. R. Wood, and C. Zaiser

Subjects
Physics, Particle physics, Annihilation, High Energy Physics::Phenomenology, Nuclear Theory, Hadron, Hyperon, General Physics and Astronomy, Lambda, Nuclear physics, Baryon, Particle decay, High Energy Physics::Experiment, Rapidity, Baryon number, Nuclear Experiment
Abstract

The production of ..lambda.. hyperons in e/sup +/e/sup -/ annihilation has been measured as a function of their total momenta, transverse momenta, and the event thrust. The total production rate is 0213 +- 0.012 +- 0.018..lambda.. or Lambda-bar per hadronic event. The observation of correlations in rapidity and angles for events with two detected ..lambda.. decays supports fragmentation models with local baryon number compensation.

Published
1985
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28. Upper limit on B00 mixing in e+e− annihilation at 29 GeV

Author

A. Baden, D. Karlen, K. Riles, T. Barklow, G. Gidal, N. S. Lockyer, J. Boyer, Darien Wood, J. Haggerty, K. Hayes, C. De La Vaissiere, Gordon H. Hanson, Andrew Lankford, C. Zaiser, A. M. Boyarski, L. Golding, G. Goldhaber, D. L. Burke, C. Matteuzi, R. A. Ong, Mark E. Nelson, F. Butler, J. M. Dorfan, D. Herrup, B. W. Leclaire, Michael Levi, V. Lüth, Roy F Schwitters, T. Schaad, M. S. Gold, R. R. Larsen, M. C. Ross, D. Amidei, G. H. Trilling, S. R. Klein, I. Juricic, J. A. Jaros, M. L. Perl, J. A. Kadyk, G. S. Abrams, W. R. Innes, Martin Breidenbach, P. D. Sheldon, Burton Richter, H. Schellman, W.B. Schmidke, R. J. Hollebeek, Patricia R. Burchat, J. M. Yelton, G. J. Feldman, L. Gladney, and P. C. Rowson

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Top quark, Annihilation, Meson, Electron–positron annihilation, Hadron, Particle Data Group, Bottom quark, Lepton
Abstract

V o l u m e 160B, n u m b e r 1,2,3 PHYSICS LETTERS 3 October 1985 UPPER LIMIT O N B°B ° MIXING IN e + e - ANNIHILATION AT 29 GeV ~ T. SCHAAD, M.E. NELSON 1, G. ABRAMS, D. AMIDEI 2, A.R. BADEN, T. BARKLOW, A.M. BOYARSKI, J. BOYER, M. BREIDENBACH, P.R. BURCHAT, D.L. BURKE, F. BUTLER, J.M. D O R F A N , G.J. FELDMAN, G. GIDAL, L. G L A D N E Y 3, M.S. GOLD, G. GOLDHABER, L. G O L D I N G 4, j. HAGGERTY, G. HANSON, K. HAYES, D. HERRUP, R.J. HOLLEBEEK, W.R. INNES, J.A. JAROS, I. JURICIC, J.A. K A D Y K , D. KARLEN, S.R. KLEIN, A.J. L A N K F O R D , R.R. LARSEN, B.W. LECLAIRE, M. LEVI 5, N.S. LOCKYER 3, V. LIJTH, C. MATTEUZZI 5, R.A. ONG, M.L. PERL, B. RICHTER, K. RILES, M.C. ROSS, P.C. ROWSON, H. SCHELLMAN 2, W.B. SCHMIDKE, R. SCHWITTERS, P.D. SHELDON, G.H. TRILLING, C. DE LA VAISSIERE 6, D.R. WOOD, J.M. YELTON 7 and C. ZAISER Stanford Linear Accelerator Center, Stanford Unwerslty, Stanford, CA 94305, USA Lawrence Berkeley Laboratory and Department of Physws, Umverstty of Cahforma, Berkeley, CA 94720, USA Department of Physws, Harvard Unwerstty, Cambridge, MA 02138, USA Recewed 21 June 1985 The rate of ddepton production m the process e+e - --* hadrons at Vs- = 29 GeV is found to be m good agreement with predictions based on semdeptomc decays of bottom and charm hadrons. We determine that the average probability for a semdeptonlc decay of a hadron lnmally containing a b quark to produce a positive lepton is less than 0 12 at the 90% confidence level and set upper hmlts on B°B ° rmxing. New knowledge of the weak mixing angles, im- posed by the long B lifetime [1,2], a lower bound on the t quark mass [3], and a small ratio [4] of F(b-*u)/ P(b ~ c), has led to predictions that B 0 mesons and, to a much lesser extent, B 0 mesons should exhibit mixing [5,6]. B 0 ~0 mixing can lead to the production of like- sign dileptons in the process e+e - ~ BOBX -> BOBX l This work was supported in part by the Department of Energy, contracts DE-AC03-76SF00515 (SLAC), DE-AC03- 76SF00098 (LBL), and DE-AC02-76ER03064 (Harvard) Present address: California Institute of Technology, Pasadena, CA 91125, USA Present address Umverslty of Chicago, Clucago, IL 60637, USA. Present address University of Pennsylvania, Pluladelptua, PA 19104, USA. Present address Therma-Wave, Inc., Fremont, CA 94539, USA. Present address: CERN, CH-1211 Geneva 23, Switzerland. Present address: LPNHE, Umverslt6 Pierre et M a n e Cune, F-75230 Pans, France Present address Oxford Umverslty, Oxford, England £ - £ - X ,1. Recently, the CLEO collaboration ,2 has reported an upper limit on B0B 0 mixing from the rate of like.sign dileptons produced in the decay of the T(4s). The UA1 collaboration [8] has observed like-sign dimuon events, leading to speculations in the literature [9] that these events could arise from B s 0 - B - 0 s mixing. In this letter, we report a measurement of dflepton rates in e+e - annihilation at an energy above the B 0 production threshold. Here, we always imply the charge conjugate reaction. We use t h e Particle Data Group convention that B (B) hadrons in t h e absence of mixing decay into positive (negative) lep- tons. The t~pes_of neutral B m e s o n s are denoted by B~ = bd and B~ = bs. The CLEO collaboration has set an upper limit on the di- lepton ratio Y n q = ( N n q n q + N~O=O)/N~O~O = N~±/N +- ~a va~a nd~d ndDd The limit set isYB~ < 0.30 at 90% C L under the assump- tion of equal semileptortic branching ratios. Since the B m e s o n s are in an l = 1 state, mixing is suppressed by inter- ference effects (see ref. [12]) a n d Y B ~ = rd, where r d = 0370-2693/85/$ 03.30 © Elsevier Science Publishers B.V. (North-Holland Physics Publishing Division)

Published
1985
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29. Measurement of theD0Lifetime

Author

J. Boyer, P. C. Rowson, L. Gladney, L. Golding, J. A. Jaros, P. D. Sheldon, G. S. Abrams, Andrew Lankford, Michael Levi, R. A. Ong, B. W. Leclaire, W. R. Innes, V. Lüth, G. H. Trilling, C. Zaiser, J. A. Kadyk, G. J. Feldman, Gordon H. Hanson, D. L. Burke, I. Juricic, D. Schlatter, Darien Wood, F. Butler, M. L. Perl, N. S. Lockyer, C. De La Vaissiere, W. B. Schmidke, J. M. Dorfan, G. Gidal, Mark E. Nelson, T. Schaad, C. Matteuzzi, M. C. Ross, D. Amidei, R. J. Hollebeek, J. M. Yelton, D. Herrup, A. M. Boyarski, Burton Richter, Patricia R. Burchat, H. Schellman, R. R. Larsen, M. S. Gold, Martin Breidenbach, G. Goldhaber, and A. Baden

Subjects
Physics, Nuclear physics, Particle decay, Annihilation, Pion, Meson, Hadron, General Physics and Astronomy, Elementary particle, Measure (mathematics)
Abstract

We have used an electronic tracking system to measure the lifetime of D0 mesons produced in e+e- annihilation at 29 GeV. Based on a sample of 27 events, the lifetime is found to be (4.2-1.0+1.3 1.0) × 10-13 s. © 1984 The American Physical Society.

Published
1984
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30. Observation ofψproduction ine+e−annihilation at 29 GeV

Author

Michael Levi, V. Lüth, F. Butler, Patricia R. Burchat, G. H. Trilling, G. Wormser, M. S. Gold, R. R. Larsen, R. J. Hollebeek, K. Riles, W. R. Innes, G. Gidal, P. C. Rowson, J. Haggerty, C. De La Vaissiere, L. Golding, Burton Richter, J. A. Kadyk, D. Karlen, I. Juricic, R. A. Ong, G. J. Feldman, Andrew Lankford, J. Boyer, D. Herrup, D. Amidei, Darien Wood, G. Goldhaber, J. A. Jaros, A. M. Boyarski, D. L. Burke, S. R. Klein, W. B. Schmidke, J. M. Dorfan, A. Baden, G. S. Abrams, T. Schaad, K. Hayes, L. Gladney, N. S. Lockyer, B. W. Leclaire, T. Barklow, C. Matteuzzi, Mark E. Nelson, P. D. Sheldon, Gordon H. Hanson, J. M. Yelton, and H. Schellman

Subjects
Nuclear physics, Physics, Cross section (physics), Annihilation, Branching fraction, Monte Carlo method, Detector, High Energy Physics::Experiment, Production (computer science), Limit (mathematics)
Abstract

Inclusive psi production in e/sup +/e/sup -/ annihilation at 29 GeV has been measured with the Mark II detector. The psi cross section is found to be 1.1 +- 0.5 +- 0.4 pb. After subtraction of the expected contribution from B decay, an upper limit of 0.02sigma/sub ..mu..//sub ..mu../ is obtained for other sources of psi production.

Published
1988
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31. Limit on the decayD0→eμ∓

Author

G. J. Feldman, J. M. Yelton, J. Haggerty, B. W. Leclaire, J. Boyer, H. Schellman, Patricia R. Burchat, Michael Levi, P. D. Sheldon, V. Lüth, Burton Richter, J. A. Jaros, R. R. Larsen, Andrew Lankford, S. R. Klein, K. Hayes, M. L. Perl, T. Himel, Mark E. Nelson, G. Gidal, A. M. Boyarski, G. Goldhaber, M. S. Gold, D. L. Burke, G. S. Abrams, W. B. Schmidke, C. Matteuzzi, D. Herrup, A. Baden, J. M. Dorfan, L. Gladney, T. Schaad, C. De La Vaissiere, T. Barklow, J. A. Kadyk, Gordon H. Hanson, G. H. Trilling, W. R. Innes, P. C. Rowson, K. Riles, D. Amidei, R. J. Hollebeek, I. Juricic, Darien Wood, F. Butler, D. Karlen, L. Golding, R. A. Ong, and N. S. Lockyer

Subjects
Physics, Nuclear physics, Particle decay, Antiparticle, Annihilation, Muon, Meson, Branching fraction, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Hadron, Analytical chemistry
Abstract

We have searched for the lepton-flavor-violating decay D/sup 0/..-->..e/sup +- /..mu../sup minus-or-plus/ in 204 pb/sup -1/ of e/sup +/e/sup -/ annihilation data at E/sub c.m./ = 29 GeV from the Mark II detector. No candidates were found; we estimate an upper limit on the cross section times branching ratio of sigma(e/sup +/e/sup -/..-->..D/sup 0/,D-bar/sup 0/; inclusive)B(D/sup 0/..-->..e/sup +- /..mu../sup minus-or-plus/) ..e/sup +- /..mu../sup minus-or-plus/)

Published
1987
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32. Search for Monojet Production ine+e−annihilation

Author

Martin Breidenbach, Kenneth G. Hayes, K. Riles, B. W. Leclaire, Burton Richter, M. E. Levi, M.C. Ross, W. R. Innes, M. S. Gold, Patricia R. Burchat, N. S. Lockyer, J. Dorfan, A. M. Boyarski, H. Schellman, I. Juricic, D. Amidei, C. Zaiser, P. D. Sheldon, A. J. Lankford, G. J. Feldman, D. Schlatter, D. L. Burke, F. Butler, Darien Wood, M. L. Perl, V. Luth, R. R. Larsen, Mark E. Nelson, W. B. Schmidke, A. Baden, R. J. Hollebeek, P. C. Rowson, T. Schaad, G. G. Hanson, D. Karlen, L. Gladney, C. Matteuzzi, J. A. Jaros, George Gidal, C. De La Vaissiere, J. Boyer, John Yelton, G. Goldhaber, L. Golding, Timothy Barklow, J. A. Kadyk, J. Haggerty, R. A. Ong, G. S. Abrams, and D. Herrup

Subjects
Quark, Nuclear physics, Physics, Particle physics, Annihilation, Electron–positron annihilation, Hadron, Higgs boson, General Physics and Astronomy, High Energy Physics::Experiment, Elementary particle, Production (computer science), Boson
Abstract

We report results of a search for events of the type e+e-jet+missing transverse momentum using the Mark II detector at PEP. Two candidate events were found, but both could come from known sources of background. A specific model for the origin of UA1 monojet events as the decay of a Z boson into two light Higgs bosons is eliminated by this search. © 1985 The American Physical Society.

Published
1985
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33. Charged multiplicity of hadronic events containing heavy-quark jets

Author

A. Baden, L. Golding, T. Barklow, R. A. Ong, C. Matteuzzi, H. Schellman, B. W. Leclaire, C. Zaiser, C. De La Vaissiere, N. S. Lockyer, J. M. Yelton, R. R. Larsen, R. J. Hollebeek, P. D. Sheldon, G. S. Abrams, W. R. Innes, D. Karlen, A. M. Boyarski, Burton Richter, Martin Breidenbach, P. C. Rowson, K. Riles, D. Schlatter, Darien Wood, J. Haggerty, J. A. Kadyk, M. E. Levi, Patricia R. Burchat, M. S. Gold, G. J. Feldman, G. H. Trilling, D. L. Burke, K. Hayes, I. Juricic, Andrew Lankford, W. B. Schmidke, J. M. Dorfan, M. C. Ross, D. Amidei, T. Schaad, D. Herrup, J. Boyer, Mark E. Nelson, Gordon H. Hanson, J. A. Jaros, G. Goldhaber, G. Gidal, M. L. Perl, V. Lüth, L. Gladney, and F. Butler

Subjects
Quark, Semileptonic decay, Physics, Particle physics, Annihilation, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, General Physics and Astronomy, Elementary particle, Charm quark, Nuclear physics, Particle decay, High Energy Physics::Experiment, Nuclear Experiment
Abstract

The charged-particle multiplicities of hadronic events deriving from produced bottom or charm quarks have been measured in the Mark II detector at PEP in e+e- annihilation at 29 GeV. For events containing one semileptonic and one hadronic weak decay, we find multiplicities of 15.20.50.7 for bottom and 13.00.50.8 for charm. The corresponding multiplicities of charged particles accompanying the pair of heavy hadrons are 5.20.50.9 for bottom, and 8.10.50.9 for charm. © 1985 The American Physical Society.

Published
1985

34. Searches for unstable neutral leptons in low-multiplicity events from electron-positron annihilation

Author

D. Karlen, J. Boyer, P. C. Rowson, John Yelton, H. Schellman, Luth, George Gidal, A. Baden, Martin Breidenbach, J. Dorfan, A. M. Boyarski, L. Golding, K. Riles, M.C. Ross, M. L. Perl, B. W. Leclaire, G. G. Hanson, D. L. Burke, Kenneth G. Hayes, R. A. Ong, W. B. Schmidke, P. D. Sheldon, D. Amidei, C. Zaiser, de la Vaissiere C, M. S. Gold, J. A. Jaros, R. J. Hollebeek, T. Schaad, G. S. Abrams, Mark E. Nelson, A. J. Lankford, C. Matteuzzi, Burton Richter, M. E. Levi, Patricia R. Burchat, G. J. Feldman, L. Gladney, Juricic I I, R. R. Larsen, D. Schlatter, Darien Wood, W. R. Innes, N. S. Lockyer, F. Butler, G. Goldhaber, Timothy Barklow, D. Herrup, J. A. Kadyk, and J. Haggerty

Subjects
Physics, Particle physics, Annihilation, Branching fraction, Electron–positron annihilation, Astrophysics::High Energy Astrophysical Phenomena, Elementary particle, Fermion, Particle identification, Nuclear physics, Particle decay, High Energy Physics::Experiment, Nuclear Experiment, Lepton
Abstract

Upper limits are given on the production of unstable neutral leptons in electron-positron annihilation at 29 GeV. The searches use selected two- and four-charged-particle events and are most sensitive to neutral-lepton masses of the order of 1 GeV/c2 and smaller. However, results are given for masses up to 14 GeV/c2. © 1985 The American Physical Society.

Published
1985
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35. Measurement of the branching fractions of the tau lepton using a tagged sample of tau decays

Author

A. J. Lankford, G. J. Feldman, Patricia R. Burchat, D. Karlen, Darien Wood, Burton Richter, J. Boyer, George H. Trilling, J. M. Yelton, D. Amidei, A. R. Baden, J. Dorfan, J. A. Kadyk, L. Golding, Michael Levi, F. Butler, I. Juricic, George Gidal, A. M. Boyarski, M. L. Perl, R. R. Larsen, W. B. Schmidke, H. Schellman, Marc Ross, Gerson Goldhaber, K. Riles, L. Gladney, Walter R. Innes, N. S. Lockyer, Kenneth G. Hayes, D. L. Burke, C. De La Vaissiere, J. Haggerty, C. Matteuzzi, C. Zaiser, P. D. Sheldon, R. A. Ong, T. Schaad, G. Hanson, R. J. Hollebeek, M. S. Gold, D. Herrup, Mark E. Nelson, P. C. Rowson, B. W. Leclaire, J. A. Jaros, G. S. Abrams, V. Luth, Timothy Barklow, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear physics, Particle physics, Pion, Annihilation, Meson, Branching fraction, Electron–positron annihilation, Hadron, High Energy Physics::Experiment, Branching (polymer chemistry), Lepton
Abstract

The branching fractions for the major decay modes of the lepton are measured from a sample of tagged decays selected from +- pairs produced in e+e- annihilation. The decay products of one member of the +- pair are used to identify the event. The opposite member of the pair is then included in the sample if it satisfies an invariant-mass cut and a charged-multiplicity cut. In this way, we attempt to select an unbiased sample of decays. The sample is divided into categories based on charged- and neutral-particle multiplicities, and charged-particle identification. The branching fractions are measured simultaneously, with an unfold technique and a maximum-likelihood fit, with the sum of the branching fractions constrained to be unity. The branching fractions for the decay modes - K- and - K*- are fixed at the world averages in the fit. The following branching fractions are measured: B(-e) =(19.10.81.1)%, B(-' - )=(18.30.90.8)%, B(-) =(10.01.1 *1,4)%, B(-0) =(25.81.72.5)%, B(-(n0, n>1))=(12.01.42.5)%, B(-+-) =(6.7 0.80.9)%, and B(-+- (n0,n>0)) =(6.10.80.9)%. The total branching fraction to one charged pion plus at least one neutral hadron is measured to be (37.81.21.0)%. Limits on allowed decay modes involving the meson are discussed. © 1987 The American Physical Society.

Published
1987

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