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57. Direct photon search by the CERES-Collaboration

Author

Baur, R., Breskin, A., Chechik, R., Drees, A., Jacob, C., Faschingbauer, U., Fischer, P., Fraenkel, Z., Gatti, E., Glässel, P., Günzel, Th., de los Heros, C. P., Hess, F., Irmscher, D., Lenkeit, B., Olsen, L. H., Panebrattsev, Y., Pfeiffer, A., Ravinovich, I., Rehak, P., Schön, A., Schukraft, J., Schukraft, J., Sampietro, M., Shor, A., Specht, H. J., Steiner, V., Tapprogge, S., Tel-Zur, G., Tserruya, I., Ullrich, Th., and Wurm, J. P.

Published
1997
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59. Современное состояние терапии быстрыми нейтронами

Author

WAGNER F.M., SPECHT H., LOEPER-KABASAKAL B., and BREITKREUTZ H.

Subjects
ТЕРАПИЯ БЫСТРЫМИ НЕЙТРОНАМИ
Abstract

В первой части статьи представлен анализ возможностей клинического применения терапии быстрыми нейтронами (ТБН), технические и статистические данные, а также биологические свойства быстрых нейтронов по сравнению с другими методами лучевой терапии. Рассматривается ситуация с клиническим применением бор-нейтрон захватной терапии (БНЗТ). Вторая часть статьи посвящена опыту применения ТБН на исследовательских реакторах FRM I и FRM II Технического университета Мюнхена в Гархинге (Германия).

Published
2015

60. Direct-photon plus away-side jet production inpp collisions at $$\sqrt s = 63$$ GeV and a determination of the gluon distribution

Author

Åkesson, T., Albrow, M. G., Almehed, S., Anassontzis, E., Batley, R., Benary, O., Bøggild, H., Botner, O., Breuker, H., Burkert, V., Callen, B., Carosi, R., Carter, A. A., Carter, J. R., Cecil, P. C., Chernyatin, V., Choi, Y., Cleland, W. E., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Dam, P., Damgaard, G., Dolgoshein, B., Eidelman, S., Evans, M. W., Fabjan, C. W., Gavrilenko, I., Goerlach, U., Goloubkov, Y., Gordon, H., Hansen, K. H., Hedberg, V., Hiddleston, J. W., Ioannou, P., Jarlskog, G., Jensen, T., Kalinovsky, A., Kantserov, V., Katsanevas, S., Kourkoumelis, C., Kroeger, R., Kulka, K., Lissauer, D., Lörstad, B., Mannelli, I., Markou, A., Mayburov, S., McCubbin, N. A., Mjörnmark, U., Møller, R., Molzon, W., Nevsky, P., Nielsen, B. S., Olsen, L. H., Oren, Y., Piskounov, G., Rahm, D. C., Resvanis, L. K., Rudge, A., Schukraft, J., Shmeleva, A., Sidorov, V., Smirnov, S., Specht, H., Starinsky, N., Stumer, I., Sullivan, M., Thodberg, H. H., Thompson, J. A., Thorstenson, G., Vanjashin, A., Vella, E., Williamson, J., Willis, W. J., Winik, M., Woody, C., and The Axial Field Spectrometer Collaboration

Published
1987
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64. Double parton scattering inpp collisions at $$\sqrt s = 63$$ GeV

Author

Åkesson, T., Albrow, M. G., Almehed, S., Benary, O., Bøggild, H., Botner, O., Breuker, H., Carter, A. A., Carter, J. R., Choi, Y., Cleland, W. E., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Damgaard, G., Fabjan, C. W., Goerlach, U., Hansen, K. H., Hedberg, V., Jarlskog, G., Katsanevas, S., Kjaer, N. J., Kroeger, R., Kulka, K., Lissauer, D., Lörstad, B., Markou, A., McCubbin, N. A., Mjörnmark, U., Møller, R., Nielsen, B. S., Olsen, L., Oren, Y., Schukraft, J., Spang, K., Specht, H., Sullivan, M., Thodberg, H. H., Thompson, J. A., Vella, E., Williamson, J., Willis, W. J., and The Axial Field Spectrometer Collaboration

Published
1987
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65. Three-jet production inpp collisions at $$\sqrt s = 63 GeV$$ and a determination of α s

Author

Åkesson, T., Albrow, M. G., Almehed, S., Batley, R., Benary, O., Bøggild, H., Botner, O., Breuker, H., Callen, B., Carter, A. A., Carter, J. R., Cecil, P., Choi, Y., Cleland, W. E., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Damgaard, G., Fabjan, C. W., Frankel, S., Frati, W., Goerlach, U., Gordon, H., Hansen, K. H., Hedberg, V., Jarlskog, G., Katsanevas, S., Kroeger, R., Kulka, K., Lissauer, D., Lörstad, B., Markou, A., McCubbin, N. A., Mjörnmark, U., Møller, R., Molzon, W., Nielsen, B. S., Olsen, L., Oren, Y., Rosselet, L., Schukraft, J., Specht, H., Stumer, I., Sullivan, M., Thodberg, H. H., Thompson, J. A., Vella, E., Williamson, J., Willis, W. J., Woody, C., Zajc, W. A., and The Axial Field Spectrometer Collaboration

Published
1986
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67. The transverse energy distribution in16O-nucleus collisions at 60 and 200 GeV per nucleon

Author

Åkesson, T., Almehed, S., Angelis, A. L. S., Armenise, N., Atherton, H., Aubry, P., Bartels, H. W., Bartley, J. H., Beaudoin, G., Beaulieu, J. M., Beker, H., Benary, O., Bettoni, D., Bisi, V., Blevis, I., Bøggild, H., Breskin, A., Chechik, R., Cleland, W., Clemen, M., Collick, B., Corriveau, F., Dagan, S., Dederichs, K., Dell'Uomo, S., Depommier, P., Devenish, R. C. E., Di Liberto, S., Di Giacomo, N., Dodd, J. R., Dolgoshein, B., Dress, A., En'yo, H., Erlandsson, B., Esten, M. J., Fabjan, C. W., Faessler, M., Fischer, P., Fraenkel, Z., Gaidot, A., Gavrilenko, I., Gibrat-Debu, F., Giubellino, P., Glässel, P., Goerlach, U., Haglund, R., Hamel, L. A., van Hecke, H., Hedberg, V., Heifetz, R., Heymann, F. F., Hölscher, A., Huber, S., Jacak, B., Jarslkog, G., Johansson, S., Kalinovski, A., Kantserov, A., Kraner, H., Kroh, V., Lamarche, F., Leroy, C., Lissauer, D., London, G., Lörstad, B., Lounis, A., Ludlam, T., Marzari-Chiesa, A., Masera, M., Mayburov, S., Mazzoni, M. A., McCubbin, M. L., McCubbin, N. A., McGaughey, P., Meddi, F., Mjörnmark, U., Muciaccia, M. T., Murray, M., Neubert, M., Nevski, P., Nilsson, S., Olsen, L., Oren, Y., Pansart, J. P., Park, Y. M., Pfeiffer, A., Piuz, F., Polychronakos, V., Poulard, G., Price, M., Rahm, D., Ramello, L., Riccati, L., Ries, H., Romano, G., Roosen, R., Rosa, G., Russ, J., Schukraft, J., Sekimoto, M., Sellden, B., Seman, M., Shmeleva, A., Shotton, P., Sidorov, V., Simone, S., Sirois, Y., Sletten, H., Smirnov, S., Soltani, J., Sondheim, W., Specht, H. J., Stumer, I., Sumarokov, A., Sunier, J., Tcherniatin, V., Thodberg, H. H., Thompson, J., Tikhomirov, V., Trent, P. T., Tserruya, I., Wigmans, R., Willis, W., and HELIOS Collaboration

Published
1988
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68. The transverse energy distribution in hadron-lead collisions

Author

Åkesson, T., Choi, Y., Dam, P., DiTorre, G., Fabjan, C. W., Franz, A., Grupen, C., Haglund, R., Kowalski, H., Kroeger, R., Lloyd, S., Mellor, D., Meyer, H. J., Mjörnmark, U., Ödingen, R., Olsen, L., Oren, Y., Schäfer, U., Schlösser, A., Specht, H., Wigmans, R., and Willis, W.

Published
1988
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69. Dijet production cross-section and fragmentation of jets produced inp p collisions at $$\sqrt s $$ =63 GeV

Author

Åkesson, T., Albrow, M. G., Almehed, S., Batley, R., Benary, O., Bøggild, H., Botner, O., Breuker, H., Callen, B., Carter, A. A., Carter, J. R., Cecil, P., Choi, Y., Cleland, W. E., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Damgaard, G., Fabjan, C. W., Frankel, S., Frati, W., Goerlach, U., Gordon, H., Hansen, K. H., Hedberg, V., Jarlskog, G., Katsanevas, S., Kroeger, R., Kulka, K., Lissauer, D., Lörstad, B., Markou, A., McCubbin, N. A., Mjörnmark, U., Møller, R., Nielsen, B. S., Olsen, L., Oren, Y., Rosselet, L., Schukraft, J., Specht, H., Stumer, I., Sullivan, M., Thodberg, H. H., Thompson, J. A., Thorstenson, G., Vella, E., Williamson, J., Willis, W. J., Woody, C., Zajc, W. A., and The Axial Field Spectrometer Collaboration

Published
1986
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71. Properties of jets in high-E T events produced inpp collisions at $$\sqrt s $$ =63 GeV

Author

Åkesson, T., Albrow, M. G., Almehed, S., Batley, R., Benary, O., Bøggild, H., Botner, O., Breuker, H., Brody, H., Burkert, V., Callen, B., Carosi, R., Carter, A. A., Carter, J. R., Cecil, P., Choi, Y., Cleland, W. E., Cockerill, D., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Dam, P., Damgaard, G., Eidelman, S., Evans, W. M., Fabjan, C. W., Frandsen, P., Frankel, S., Frati, W., Gibson, M., Goerlach, U., Gordon, H., Hansen, K. H., Hedberg, V., Hiddleston, J., Hilke, H. J., Hooper, J., Jarlskog, G., Jeffreys, P., Jensen, T., Kalinovsky, A., Kesseler, G., Killian, T., Kroeger, R., Kulka, K., Lans, J. v. d., Lindsay, J., Lissauer, D., Lörstad, B., Ludlam, T., Markou, A., McCubbin, N. A., Mjörnmark, U., Møller, R., Molzon, W., Nielsen, B. S., Nilsson, A., Olsen, L. H., Oren, Y., Rosselet, L., Rosso, E., Rudge, A., Schindler, R., Specht, H., Stumer, I., Sullivan, M., Thompson, J., Thorstenson, G., Vella, E., Williamson, J., Willis, W. J., Winik, M., Witzeling, W., Woody, C., Zajc, W. A., and The Axial Field Spectrometer Collaboration

Published
1984
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76. Transverse energy distributions in16O-nucleus collisions

Author

Corriveau, F., Åkesson, T., Almehed, S., Angelis, A. L. S., Armenise, N., Atherton, H., Aubry, P., Bartels, H. W., Bartley, J. H., Beaudoin, G., Beaulieu, J. M., Beker, H., Benary, O., Bettoni, D., Bisi, V., Blevis, I., Bøggild, H., Breskin, A., Chechik, R., Cleland, W., Clemen, M., Collick, B., Dagan, S., Dederichs, K., Dell'Uomo, S., Depommier, P., Devenish, R. C. E., DiLiberto, S., DiGiacomo, N., Dodd, J. R., Dolgoshein, B., Dress, A., En'yo, H., Erlandsson, B., Esten, M. J., Fabjan, C. W., Faessler, M., Fischer, P., Fraenkel, Z., Gaidot, A., Gavrilenko, I., Gibrat-Debu, F., Giubellino, P., Glässel, P., Goerlach, U., Haglund, R., Hamel, L. A., van Hecke, H., Hedberg, V., Heifetz, R., Heymann, F. F., Hölscher, A., Huber, S., Jacak, B., Jarlskog, G., Johansson, S., Kalinovski, A., Kantserov, A., Kramer, H., Kroh, V., Lamarche, F., Leroy, C., Lissauer, D., London, G., Lörstad, B., Lounis, A., Ludlam, T., Marzari-Chiesa, A., Masera, M., Mayburov, S., Mazzoni, M. A., McCubbin, M. L., McCubbin, N. A., McGaughey, P., Meddi, F., Mjörnmark, U., Muciaccia, M. T., Murray, M., Neubert, M., Nevski, P., Nilsson, S., Olsen, L., Oren, Y., Pansart, J. P., Park, Y. M., Pfeiffer, A., Piuz, F., Polychronakos, V., Poulard, G., Price, M., Rahm, D., Ramello, L., Riccati, L., Ries, H., Romano, G., Roosen, R., Rosa, G., Russ, J., Schukraft, J., Sekimoto, M., Sellden, B., Seman, M., Shmeleva, A., Shotton, P., Sidorov, V., Simone, S., Sirois, Y., Sletten, H., Smirnov, S., Soltani, J., Sondheim, W., Specht, H. J., Stumer, I., Sumarokov, A., Sunier, J., Tcherniatin, V., Thodberg, H. H., Thompson, J., Tikhomirov, V., Trent, P. T., Tserruya, I., Wigmans, R., Willis, W., and HELIOS Collaboration

Published
1988
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78. A study of the production of two direct photons inpp collisions at the CERN ISR

Author

Åkesson, T., Albrow, M. G., Almehed, S., Anassontzis, E., Batley, R., Benary, O., Boggild, H., Botner, O., Breuker, H., Burkert, V., Callen, B., Carosi, R., Carter, A. A., Carter, J. R., Cecil, P. C., Chernyatin, V., Choi, Y., Cleland, W. E., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Dam, P., Damgaard, G., Dolgoshein, B., Eidelman, S., Evans, W. M., Fabjan, C. W., Frankel, S., Frati, W., Gavrilenko, I., Goerlach, U., Goloubdov, Y., Gordon, H., Hansen, K. H., Hedberg, V., Hiddleston, J. W., Jarlskog, G., Jensen, T., Kalinovsky, A., Kantserov, V., Katsanevas, S., Kourkoumelis, C., Kroeger, R., Kulka, K., Lissauer, D., Lorstad, B., Mannelli, I., Markou, A., Mayburov, S., McCubbin, N. A., Mjornmark, U., Moller, R., Molzon, W., Nevsky, P., Nielsen, B. S., Olsen, L. H., Oren, Y., Piskounov, G., Resvanis, L. K., Rudge, A., Schukraft, J., Shmeleva, A., Sidorov, V., Specht, H., Stumer, I., Sullivan, M., Thompson, J. A., Thorstenson, G., Vasiliev, P., Vella, E., Williamson, J., Willis, W. J., Woody, C., Zajc, W. A., and The Axial Field Spectrometer Collaboration

Published
1986
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83. Low Mass Dimuon Production in p-A Collisions at $\sqrt{s} = 27.5$ GeV with NA60

Author

Uras, A., Arnaldi, R, Oppedisano, C, Scomparin, E, Banicz, K, Damjanovic, S, David, A, Forster, A, Guettet, N, Keil, M, Lourenco, C, Martins, P, Radermacher, E, Ramalhete, P, Rosinsky, P, Shahoyan, R, Specht, H J, Castor, J, Devaux, A, Fargeix, J, Seixas, J, Sonderegger, P, Gulkanian, H, Poghosyan, T, Heuser, J M, Guichard, A, Floris, M, Li, Z, Force, P, Ferretti, A, En'yo, H, Ducroux, L, de Falco, A, Colla, A, Cortese, P, Cicalo, C, Pillot, P, Chaurand, B, Ohnishi, H, Parracho, P, Puddu, G, Veenhof, R, Serci, S, Lozano, J, Usai, G, Wohri, H K, Tieulent, R, Masoni, A, Neves, A, Manso, F, ALICE, Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), and NA60

Subjects
Nuclear and High Energy Physics, Proton, Meson, Nuclear Theory, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Spectral line, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, Large Hadron Collider, Muon, 010308 nuclear & particles physics, Nuclear matter, Pair production, Mass spectrum, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract

The NA60 experiment has studied low-mass muon pair production in proton-nucleus collisions with a system of Be, Cu, In, W, Pb and U targets using a 400 GeV/$c$ proton beam at the CERN SPS. The mass spectrum is well described by the superposition of the two-body and Dalitz decays of the light neutral mesons $\eta$, $\rho$, $\omega$, $\eta'$ and $\phi$. A new high-precision measurement of the electromagnetic transition form factors of the $\eta$ and $\omega$ mesons is presented, complemented with a measurement of the temperature parameter of the $\rho$ meson in cold nuclear matter. The $\pt$ spectra for the $\omega$ and $\phi$ mesons are extracted in the full $\pt$ range accessible, up to $\pt = 2$ GeV/$c$. The nuclear dependence of the production cross sections for the $\eta$, $\omega$ and $\phi$ mesons has been investigated in terms of the power law $\sigma_\mathrm{pA} \propto \mathrm{A}^\alpha$, and the $\alpha$ parameter was studied as a function of $\pt$. The NA60 experiment has studied low-mass muon pair production in proton-nucleus collisions with a system of Be, Cu, In, W, Pb and U targets using a 400 GeV/$c$ proton beam at the CERN SPS. The mass spectrum is well described by the superposition of the two-body and Dalitz decays of the light neutral mesons $\eta$, $\rho$, $\omega$, $\eta'$ and $\phi$. A new high-precision measurement of the electromagnetic transition form factors of the $\eta$ and $\omega$ mesons is presented, complemented with a measurement of the temperature parameter of the $\rho$ meson in cold nuclear matter. The $\pt$ spectra for the $\omega$ and $\phi$ mesons are extracted in the full $\pt$ range accessible, up to $\pt = 2$ GeV/$c$. The nuclear dependence of the production cross sections for the $\eta$, $\omega$ and $\phi$ mesons has been investigated in terms of the power law $\sigma_\mathrm{pA} \propto \mathrm{A}^\alpha$, and the $\alpha$ parameter was studied as a function of $\pt$.

Published
2011
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84. A comparative measurement of ϕ→K+K− and ϕ→μ+μ− in In–In collisions at the CERN SPS

Author

Arnaldi, R., Banicz, K., Castor, J., Chaurande, B., Chen, W., Cicalò, C., Colla, A., Cortese, P., Damjanovic, S., David, A., de Falco, A., Devaux, A., Ducroux, L., Enʼyo, H., Fargeix, J., Ferretti, Alessandro, Floris, M., Förster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J. M., Keil, M., Lif, Z., Lourenço, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Uras, A., Usai, G., Veenhof, R., and Wöhri, H. K.

Published
2011

85. A comparative measurement of $��\rightarrow K^+K^-$ and $��\rightarrow ��^+��^-$ in In-In collisions at the CERN SPS

Author

NA60 Collaboration, Arnaldi, R., Banicz, K., Castor, J., Chaurand, B., Chen, W., Cical��, C., Colla, A., Cortese, P., Damjanovic, S., David, A., de Falco, A., Devaux, A., Ducroux, L., En'yo, H., Fargeix, J., Ferretti, A., Floris, M., F��rster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J. M., Keil, M., Li, Z., Louren��o, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Uras, A., Usai, G., Veenhof, R., and W��hri, H. K.

Subjects
Nuclear Theory, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

The NA60 experiment at the CERN SPS has studied $��$ meson production in In-In collisions at 158A GeV via both the $K^+K^-$ and the $��^+��^-$ decay channels. The yields and inverse slope parameters of the $m_T$ spectra observed in the two channels are compatible within errors, different from the large discrepancies seen in Pb-Pb collisions between the hadronic (NA49) and dimuon (NA50) decay channels. Possible physics implications are discussed.

Published
2011
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89. phi production in In-In collisions at 158-A-GeV

Author

Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., David, A., De Falco, A., Devaux, A., Ducroux, L., En'Yo, H., Fargeix, J., Ferretti, Alessandro, Floris, M., Forster, A., Force, P., Guettet, N., Guichard, A., Gulkanyan, H., Heuser, J., Keil, M., Li, Z., Lourenco, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Uras, A., Usai, G., Veenhof, R., and Wohri, H. K.

Published
2010

90. J/psi production in proton-nucleus collisions at 158 and 400 GeV

Author

Arnaldi, R, Banicz, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., David, A., de Falco, A., Devaux, A., En'yo, H., Fargeix, J., Ferretti, A., Floris, M., Foerster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J.M., Keil, M., Li, Z., Lourenco, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H.J., Uras, A., Usai, G., Veenhof, R., Woehri, H.K., Banicz, K, Castor, J, Chaurand, B, Chen, W, Cical, C, Colla, A, Cortese, P, Damjanovic, S, David, A, de Falco, A, Devaux, A, Ducroux, L, En'yo, H, Fargeix, J, Ferretti, A, Floris, M, Frster, A, Force, P, Guettet, N, Guichard, A, Gulkanian, H, Heuser, J M, Keil, M, Li, Z, Lourenco, C, Lozano, J, Manso, F, Martins, P, Masoni, A, Neves, A, Ohnishi, H, Oppedisano, C, Parracho, P, Pillot, P, Poghosyan, T, Puddu, G, Radermacher, E, Ramalhete, P, Rosinsky, P, Seixas, J, Serci, S, Shahoyan, R, Sonderegger, P, Specht, H J, Tieulent, R, Uras, A, Usai, G, Veenhof, R, Woehri, H K, Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), NA60, Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Proton, 010308 nuclear & particles physics, Hadron, Nuclear Theory, FOS: Physical sciences, Parton, Elementary particle, Fermion, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Momentum, Baryon, 0103 physical sciences, Nuclear Physics - Experiment, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), 010306 general physics, Nucleon, Nuclear Experiment
Abstract

The NA60 experiment has studied J/psi production in p-A collisions at 158 and 400 GeV, at the CERN SPS. Nuclear effects on the J/psi yield have been estimated from the A-dependence of the production cross section ratios sigma_{J/psi}^{A}/sigma_{J/psi}^{Be} (A=Al, Cu, In, W, Pb, U). We observe a significant nuclear suppression of the J/psi yield per nucleon-nucleon collision, with a larger effect at lower incident energy, and we compare this result with previous observations by other fixed-target experiments. An attempt to disentangle the different contributions to the observed suppression has been carried out by studying the dependence of nuclear effects on x_2, the fraction of nucleon momentum carried by the interacting parton in the target nucleus., Comment: NA60 Collaboration, accepted for publication by Phys. Lett. B

Published
2010
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91. Evidence for the production of thermal-like muon pairs with masses above 1-GeV/c**2 in 158-A-GeV Indium-Indium Collisions

Author

Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., Andre, David, de Falco, A., Devaux, A., Ducroux, L., Enyo, H., Fargeix, J., Ferretti, Alessandro, Floris, M., Force, P., Forster, A., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J., Keil, M., Kluberg, L., Li, Z., Lourenco, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Usai, G., Veenhof, R., and H. Wohri .

Published
2009

92. Evidence for the production of thermal-like muon pairs with masses above 1 GeV/c^2 in 158A GeV Indium-Indium Collisions

Author

NA60 Collaboration, Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., David, A., de Falco, A., Devaux, A., Ducroux, L., Enyo, H., Fargeix, J., Ferretti, A., Floris, M., Forster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J. M., Keil, M., Kluberg, L., Li, Z., Lourenco, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Usai, G., Veenhof, R., Wohri, H. K., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), NA60, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
14.40.Lb - 25.75.Nq - 25.75.Cj, Physics::Instrumentation and Detectors, Computer Science::Information Retrieval, Nuclear Theory, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Physics::Accelerator Physics, Nuclear Physics - Experiment, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

The yield of muon pairs in the invariant mass region 1, Comment: 16 pages, 19 figures

Published
2009
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94. phi Production in In-In Collisions at 158-A-GeV

Author

Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalò, C., Colla, A., Cortese, P., Damjanovic, S., David, A., de Falco, A., Devaux, A., Ducroux, L., En’yo, H., Fargeix, J., Ferretti, A., Floris, M., Förster, A., Force, P., Guettet, N., Guichard, A., Gulkanyan, H., Heuser, J., Keil, M., Kluberg, L., Li, Z., Lourenço, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Uras, A., Usai, G., Veenhof, R., Wöhri, H. K., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), NA60, Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
NA60, Particle physics, SPS ENERGIES, Physics and Astronomy (miscellaneous), MESON PRODUCTION, STRANGENESS, INDIUM-INDIUM COLLISIONS, HEAVY-ION COLLISIONS, 01 natural sciences, Spectral line, High Energy Physics - Experiment, QUARK-GLUON PLASMA, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], DETECTORS, Rapidity, 010306 general physics, Nuclear Experiment, NUCLEON, Engineering (miscellaneous), Physics, Muon, Large Hadron Collider, RADIATION, 010308 nuclear & particles physics, Coupling (probability), Pair production, High Energy Physics::Experiment, Centrality, Particle Physics - Experiment, Energy (signal processing)
Abstract

The NA60 experiment has measured muon pair production in In-In collisions at 158 AGeV at the CERN SPS. This paper presents a high statistics measurement of $\phi\to\mu\mu$ meson production. Differential spectra, yields, mass and width are measured as a function of centrality and compared to previous measurements in other colliding systems at the same energy. The width of the rapidity distribution is found to be constant as a function of centrality, compatible with previous results. The decay muon polar angle distribution is measured in several reference frames. No evidence of polarization is found as a function of transverse momentum and centrality. The analysis of the $p_{T}$ spectra shows that the $\phi$ has a small radial flow, implying a weak coupling to the medium. The $T_{eff}$ parameter measured in In-In collisions suggests that the high value observed in Pb-Pb in the kaon channel is difficult to reconcile with radial flow alone. The absolute yield is compared to results in Pb-Pb collisions: though significantly smaller than measured by NA50 in the muon channel, it is found to exceed the NA49 and CERES data in the kaon channel at any centrality. The mass and width are found to be compatible with the PDG values at any centrality and at any $p_{T}$: no evidence for in-medium modifications is observed., Comment: 18 pages, 18 figures, accepted for publication in EPJ C

Published
2009
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95. Study of the electromagnetic transition form-factors in \eta -> \mu^+\mu^-\gamma and \omega -> \mu^+\mu^-\pi^0 decays with NA60

Author

Arnaldi, R., Banicz, K., Castor, J., Chaurand, B., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., Andre, David, de Falco, A., Devaux, A., Ducroux, L., Enyo, H., Fargeix, J., Ferretti, Alessandro, Floris, M., Force, P., Forster, A., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J., Keil, M., Kluberg, L., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Usai, G., Veenhof, R., Wohri, H., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), NA60, Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Lepton pairs, Transition form factor, Conversion decays, High Energy Physics - Phenomenology, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Phenomenology
Abstract

The NA60 experiment at the CERN SPS has studied low-mass muon pairs in 158A GeV In-In collisions. The mass and pT spectra associated with peripheral collisions can quantitatively be described by the known neutral meson decays. The high data quality has allowed to remeasure the electromagnetic transition form factors of the Dalitz decays \eta -> \mu^+\mu^-\gamma and \omega -> \mu^+\mu^-\pi^0. Using the usual pole approximation F = (1-M_{\mu\mu}^{2}/\Lambda^{2})^{-1} for the form factors, we find \Lambda^{-2} (in GeV^{-2}) to be 1.95+-0.17(stat.)+-0.05(syst.) for the \eta and 2.24+-0.06(stat.)+-0.02(syst.) for the \omega. While the values agree with previous results from the Lepton-G experiment, the errors are greatly improved, confirming now on the level of 10\sigma the strong enhancement of the \omega form factor beyond the expectation from vector meson dominance. An improved value of the branching ratio BR(\omega -> \mu^+\mu^-\pi^0) = [1.73+-0.25(stat.)+-0.14(syst.)]*10^{-4} has been obtained as a byproduct., Comment: Submitted to Phys. Lett. B

Published
2009
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96. Thermal Dimuon Emission in In-In at the CERN SPS

Author

Arnaldi, R., Banicz, K., Castor, J., Chaurand, B., Cicalò, C., Colla, A., Cortese, P., Damjanovic, S., David, A., De Falco, A., Devaux, A., Ducroux, L., Enyo, H., Ferretti, J., Fargeix, A., Floris, M., Förster, A., Force, P., Guettet, N., Guichard, A., R. Gulkanian, H., Heuser, J., Keil, M., Kluberg, L., Lourenço, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, Philippe, Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., J. Specht, H., Tieulent, R., Usai, G., Veenhof, R., K. Wöhri, H., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), NA60, Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
presenté par M. Floris, FOS: Physical sciences, Nuclear Physics - Experiment, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract

The NA60 experiment at the CERN SPS has studied low-mass dimuon production in 158A GeV In-In collisions. A significant excess of pairs is observed above the yield expected from neutral meson decays, consistent with a dominant contribution from $\pi\pi\to\rho\to\mu\mu$. This paper presents precision results on the mass and transverse momentum spectra of the excess pairs. The space-time averaged rho spectral function associated to the measured mass distribution shows a significant broadening, but essentially no mass shift. The slope parameter $T_{eff}$ extracted from the spectra rises with dimuon mass up to the $\rho$, followed by a sudden decline above. While the initial rise is consistent with the expectations for radial flow of a hadronic decay source, the decline indicates a transition to an emission source with much smaller flow, possibly of partonic origin., Comment: 4 pages, 4 figures, presented at the XLIIIth Rencontres de Moriond

Published
2008

97. Highlights from NA60

Author

De Falco, A., Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., David, A., Devaux, A., Ducroux, L., En'Yo, H., Fargeix, J., Ferretti, A., Floris, M., Force, P., Forster, A., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J., Keil, M., Kluberg, L., Li, Zhenyu, Lourenço, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, Philippe, Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Usai, G., Veenhof, R., Wöhri, H., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), NA60, Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Nuclear Theory, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment, High Energy Physics - Experiment
Abstract

NA60 measured dimuon production in p-A and In-In collisions at the CERN SPS. This paper presents a high statistics measurement of $\phi$ meson production in In-In collisions at 158 AGeV. Both the transverse momentum, rapidity, decay angular distributions and the absolute yield were measured as a function of centrality. The results are compared to previous measurements in order to shed light on the long standing $\phi$ puzzle. In addition, highlights on $\eta$ meson production and on the dimuon excess below the J/$\psi$ mass are presented., Comment: 8 pages, 6 figures, proceedings of the Strangeness in Quark Matter 2008 conference (SQM08), Beijing, Oct.6-10, 2008

Published
2008
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98. NA60 results on quarkonia

Author

Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., David, A., De Falco, A., Devaux, A., Ducroux, L., En'Yo, H., Fargeix, J., Ferretti, A., Floris, M., Foerster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., M. Heuser, J., Keil, M., Kluberg, L., Li, Zhenyu, Lourenco, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, Philippe, Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., J. Specht, H., Tieulent, R., Usai, G., Veenhof, R., K. Woehri, H., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), NA60, Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2008

99. Thermal dileptons at SPS energies

Author

Damjanovic, S., Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., David, A., De Falco, A., Devaux, A., Ducroux, L., En'Yo, H., Fargeix, J., Ferretti, A., Floris, M., Foerster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., M. Heuser, J., Keil, M., Kluberg, L., Li, Zhenyu, Lourenco, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, Philippe, Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., J. Specht, H., Tieulent, R., Usai, G., Veenhof, R., K. Woehri, H., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and NA60

Subjects
Physics, Nuclear and High Energy Physics, Annihilation, 010308 nuclear & particles physics, Hadron, FOS: Physical sciences, Radiation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Polarization (waves), 01 natural sciences, Spectral line, Nuclear physics, Thermal radiation, 0103 physical sciences, Mass spectrum, High Energy Physics::Experiment, Nuclear Physics - Experiment, Charm (quantum number), Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment
Abstract

Clear signs of excess dileptons above the known sources were found at the SPS since long. However, a real clarification of these observations was only recently achieved by NA60, measuring dimuons with unprecedented precision in 158A GeV, In-In collisions. The excess mass spectrum in the region M rho -> mu+mu- annihilation. The associated rho spectral function shows a strong broadening, but essentially no shift in mass. In the region M>1 GeV, the excess is found to be prompt, not due to enhanced charm production. The inverse slope parameter Teff associated with the transverse momentum spectra rises with mass up to the rho, followed by a sudden decline above. While the initial rise, coupled to a hierarchy in hadron freeze-out, points to radial flow of a hadronic decay source, the decline above signals a transition to a low-flow source, presumably of partonic origin. The mass spectra show at low transverse momenta the steep rise towards low masses characteristic for Planck-like radiation. The polarization of the excess referred to the Collins Soper frame is found to be isotropic. All observations are consistent with the interpretation of the excess as thermal radiation., Prepared for 20th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions: Quark Matter 2008 (QM2008), Jaipur, India, 4-10 Feb. 2008

Published
2008
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100. Phi production in In-In collisions and the phi puzzle

Author

Floris, M., Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., David, A., de Falco, A., Devaux, A., Ducroux, L., En'Yo, H., Fargeix, J., Ferretti, A., Foerster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., M. Heuser, J., Keil, M., Kluberg, L., Li, Zhenyu, Lourenco, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, Philippe, Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., J. Specht, H., Tieulent, R., Usai, G., Veenhof, R., K. Woehri, H., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and NA60

Subjects
Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract

International audience; The NA60 experiment measured dimuon production in In-In collisions at 158 A GeV. This paper presents a high statistics measurement of phi → μμ with the specific objective to provide an insight into the phi puzzle, i.e. the difference in the inverse T slopes and absolute yields measured by NA49 and NA50 in the kaon and lepton channel, respectively. Transverse momentum distributions were studied as a function of centrality. The slope parameter T shows a rapid increase with centrality, followed by a saturation. Variations of T with the fit range of the order of 15 MeV were observerd, possibly as a consequence of radial flow. The phi meson yield normalized to the number of participants increases with centrality and is consistently higher than the yield measured by the NA49 experiment at any centrality

Published
2008
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