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103 results on '"P. Force"'

1. Nuclear dependence of light neutral meson production in p-A collisions at 400 GeV with NA60

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., Gulkanian, H., Heuser, J. M., Jarron, P., 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., and Wöhri, H. K.

Subjects
High Energy Physics - Experiment, Nuclear 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 proton beam at the CERN SPS. The transverse momentum spectra of the $\rho/\omega$ and $\phi$ mesons are measured in the full $p_\mathrm{T}$ range accessible, from $p_\mathrm{T} = 0$ up to 2 GeV/$c$. The nuclear dependence of the production cross sections of the $\eta$, $\omega$ and $\phi$ mesons has been found to be consistent with the power law $\sigma_\mathrm{pA} \propto \mathrm{A}^\alpha$, with the $\alpha$ parameter increasing as a function of $p_\mathrm{T}$ for all the particles, and an approximate hierarchy $\alpha_\eta \approx \alpha_\phi > \alpha_\omega$. The cross section ratios $\sigma_\eta/\sigma_\omega$, $\sigma_\rho/\sigma_\omega$ and $\sigma_\phi/\sigma_\omega$ have been studied as a function of the size A of the production target, and an increase of the $\eta$ and $\phi$ yields relative to the $\omega$ is observed from p-Be to p-U collisions.

Published
2020
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2. Structure of unbound neutron-rich $^{9}$He studied using single-neutron transfer

Author

Kalanee, T. Al, Gibelin, J., Roussel-Chomaz, P., Keeley, N., Beaumel, D., Blumenfeld, Y., Fernandez-DomÄ{\pm}nguez, B., Force, C., Gaudefroy, L., Gillibert, A., Guillot, J., Iwasaki, H., Krupko, S., Lapoux, V., Mittig, W., Mougeot, X., Nalpas, L., Pollacco, E., Rusek, K., Roger, T., Savajols, H., De Séréville, N., Sidorchuk, S., Suzuki, D., Strojek, I., and Orr, N. A.

Subjects
Nuclear Experiment
Abstract

The 8He(d,p) reaction was studied in inverse kinematics at 15.4A MeV using the MUST2 Si-CsI array in order to shed light on the level structure of 9He. The well known 16O(d,p)17O reaction, performed here in reverse kinematics, was used as a test to validate the experimental methods. The 9He missing mass spectrum was deduced from the kinetic energies and emission angles of the recoiling protons. Several structures were observed above the neutron-emission threshold and the angular distributions were used to deduce the multipolarity of the transitions. This work confirms that the ground state of 9He is located very close to the neutron threshold of 8He and supports the occurrence of parity inversion in 9He., Comment: Exp\'erience GANIL/SPIRAL1/MUST2

Published
2013
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3. Study of $^{124}$Sn+$^{136}$Xe fusion-evaporation: analysis of a rare-event experiment

Author

Avez, Benoît, Drouart, Antoine, Stodel, Ch., Simenel, Cédric, Alcantara, J., Adamczyk, M., Banka, P., Bonnet, E., Clément, E., Dayras, R., Force, C., Golabek, C., Gonciarz, A., Grevy, S., Hauschild, K., Jacquet, D., Korichi, A., Kozik, T., Lazko, P., Morjean, M., Popeko, A., Roger, T., Saint-Laurent, M. -G., Sosin, Z., Sulignano, B., Theisen, C., Wieloch, A., Yeremin, A., Yilmaz, B., and Zielinska, M.

Subjects
Nuclear Experiment
Abstract

Fusion-evaporation in the $^{124}$Sn+$^{136}$Xe system is studied using a high intensity xenon beam provided by the Ganil accelerator and the LISE3 wien filter for the selection of the products. Due to the mass symmetry of the entrance system, the rejection of the beam by the spectrometer was of the order of $5times10^8$. We have thus performed a detailed statistical analysis to estimate random events and to infer the fusion-evaporation cross sections. No signicant decay events were detected and upper limit cross sections of 172 pb, 87 pb and 235 pb were deduced for the synthesis of $^{257}$Rf, $^{258}$Rf and $^{259}$Rf, respectively., Comment: 7 pages, 4 figures

Published
2011

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

Author

NA60 Collaboration, Arnaldi, R., Banicz, 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., Gulkanian, H., Heuser, J. M., Keil, M., 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., and Wöhri, H. K.

Subjects
Nuclear Experiment
Abstract

The NA60 experiment at the CERN SPS has studied $\phi$ meson production in In-In collisions at 158A GeV via both the $K^+K^-$ and the $\mu^+\mu^-$ 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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5. Emergence of the N=16 shell gap in 21O

Author

Fernandez-Dominguez, B., Thomas, J. S., Catford, W. N., Delaunay, F., Brown, S. M., Orr, N. A., Rejmund, M., Achouri, N. L., Falou, H. Al, Ashwood, N. A., Beaumel, D., Blumenfeld, Y., Brown, B. A., Chapman, R., Chartier, M., Curtis, N., Force, C., de France, G., Franchoo, S., Guillot, J., Haigh, P., Hammache, F., Labiche, M., Lapoux, V., Lemmon, R. C., Marechal, F., Moro, A., Martin, B., Mougeot, X., Mouginot, B., Nalpas, L., Navin, A., Patterson, N., Pietras, B., Pollacco, E. C., Leprince, A., Ramus, A., Scarpaci, J. A., de Séréville, N., Stefan, I., Sorlin, O., and Wilson, G.

Subjects
Nuclear Experiment
Abstract

The spectroscopy of 21O has been investigated using a radioactive 20O beam and the (d,p) reaction in inverse kinematics. The ground and first excited states have been determined to be Jpi=5/2+ and Jpi=1/2+ respectively. Two neutron unbound states were observed at excitation energies of 4.76 +- 0.10 and 6.16 +- 0.11. The spectroscopic factor deduced for the lower of these interpreted as a 3/2+ level, reveals a rather pure 0d3/2 single-particle configuration. The large energy difference between the 3/2+ and 1/2+ states is indicative of the emergence of the N=16 magic number. For the higher lying resonance, which has a character consistent with a spin-parity assignment of 3/2+ or 7/2-, a 71% branching ratio to the first 2+ state in 20O has been observed. The results are compared with new shell model calculations., Comment: 5 pages, 2 figures

Published
2010
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6. Prolate-Spherical Shape Coexistence at N=28 in $^{44}$S

Author

Force, C., Grévy, S., Gaudefroy, L., Sorlin, O., Caceres, L., Rotaru, F., Mrazek, J., Achouri, N. L., Angélique, J. C., Azaiez, F., Bastin, B., Borcea, R., Buta, A., Daugas, J. M., Dlouhy, Z., Dombradi, Zs., De Oliveira, F., Negoita, F., Penionzhkevich, Y., Saint-Laurent, M. G., Sohler, D., Stanoiu, M., Stefan, I., Stodel, C., and Nowacki, F.

Subjects
Nuclear Experiment
Abstract

The structure of $^{44}$S has been studied using delayed $\gamma$ and electron spectroscopy at \textsc{ganil}. The decay rates of the 0$^+_2$ isomeric state to the 2$^+_1$ and 0$^+_1$ states have been measured for the first time, leading to a reduced transition probability B(E2~:~2$^{+}_1$$\rightarrow$0$^{+}_2)$= 8.4(26)~e$^2$fm$^4$ and a monopole strength $\rho^2$(E0~:~0$^{+}_2$$\rightarrow$0$^{+}_1)$ =~8.7(7)$\times$10$^{-3}$. Comparisons to shell model calculations point towards prolate-spherical shape coexistence and a phenomenological two level mixing model is used to extract a weak mixing between the two configurations., Comment: 5 pages, 3 figures, accepted for publication in Physical Review Letters

Published
2010
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7. 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., Ducroux, L., 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., Tieulent, R., Uras, A., Usai, G., Veenhof, R., and Woehri, H. K.

Subjects
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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8. NA60 results on thermal dimuons

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., En'yo, H., Fargeix, J., Ferretti, A., Floris, M., Foerster, 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., and Woehri, H. K.

Subjects
Nuclear Experiment
Abstract

The NA60 experiment at the CERN SPS has measured muon pairs with unprecedented precision in 158A GeV In-In collisions. A strong excess of pairs above the known sources is observed in the whole mass region 0.2 rho -> mu+mu- annihilation. The associated rho spectral function shows a strong broadening, but essentially no shift in mass. For M>1 GeV, the excess is found to be prompt, not due to enhanced charm production, with pronounced differences to Drell-Yan pairs. The slope parameter Teff associated with the transverse momentum spectra rises with mass up to the rho, followed by a sudden decline above. The rise for M<1 GeV is consistent with radial flow of a hadronic emission source. The seeming absence of significant flow for M>1 GeV and its relation to parton-hadron duality is discussed in detail, suggesting a dominantly partonic emission source in this region. A comparison of the data to the present status of theoretical modeling is also contained. The accumulated empirical evidence, including also a Planck-like shape of the mass spectra at low pT and the lack of polarization, is consistent with a global interpretation of the excess dimuons as thermal radiation. We conclude with first results on omega in-medium effects., Comment: 10 pages, 12 figures, submitted to Eur. Phys. J. C

Published
2008
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9. First results on angular distributions of thermal dileptons in nuclear 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., En'yo, H., Fargeix, J., Ferretti, A., Floris, M., Foerster, 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., and Woehri, H. K.

Subjects
Nuclear Experiment
Abstract

The NA60 experiment at the CERN SPS has studied dimuon production in 158A GeV In-In collisions. The strong excess of pairs above the known sources found in the complete mass region 0.2

Published
2008
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10. Evidence for the production of thermal 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., and Wohri, H. K.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

The yield of muon pairs in the invariant mass region 1

Published
2008
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11. Highlights from the NA60 experiment

Author

Ferretti, A., Arnaldi, R., Averbeck, R., Banicz, K., Castor, J., Chaurand, B., Cicalò, C., Colla, A., Cortese, P., Damjanovic, S., David, A., De Falco, A., Devaux, A., Drees, A., Ducroux, L., En'yo, H., Floris, M., Förster, A., Force, P., Guettet, N., Guichard, A., Gulkanyan, H., Heuser, J. M., Keil, M., Kluberg, L., Lourenço, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., 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 Wöhri, H.

Subjects
Nuclear Experiment
Abstract

The NA60 experiment is a fixed-target experiment at the CERN SPS. It has measured the dimuon yield in Indium--Indium collisions with an In beam of 158 AGeV/c and in p-A collisions with a proton beam of 400 and 158 AGeV/c. The results allow to address three important physics topics, namely the study of the rho spectral function in nuclear collisions, the clarification of the origin of the dimuon excess measured by NA50 in the intermediate mass range, and the J/psi suppression pattern in a collision system different from Pb-Pb. An overview of these results will be given in this paper., Comment: 4 pages, 6 figures, proceeding for the Rencontres de Moriond - QCD and Hadronic interactions - La Thuile (Italy), March 17-24 2007

Published
2007

12. J/$\psi$ suppression in In-In collisions at 158 GeV/nucleon

Author

Arnaldi, R., Arnaldi, NA60 Collaboration R., Averbeck, R., Banicz, K., Castor, J., Chaurand, B., Cicalo', C., Colla, A., Cortese, P., Damjanovic, S., David, A., DeFalco, A., Devaux, A., Drees, A., Ducroux, L., En'yo, H., Ferretti, A., Floris, M., Forster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J., Keil, M., Kluberg, L., Lourenco, C., Lozano, J., Manso, F., Masoni, A., Martins, P., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., 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 Wohri, H. K.

Subjects
Nuclear Experiment
Abstract

The NA60 experiment has studied J/$\psi$ production in Indium-Indium collisions at 158 A$\cdot$GeV. In this paper we present an updated set of results obtained with the complete set of available statistics and an improved alignment of the vertex tracker. The centrality dependence of the J/$\psi$ production, obtained with an analysis technique based only on the J/$\psi$ sample, indicates that a suppression beyond that induced by nuclear absorption is present in In-In collisions, setting in at $\sim$80 participant nucleons. A first study of the systematic errors related with this measurement is discussed. We also present preliminary results on the J/$\psi$ azimuthal distributions., Comment: 8 pages, 3 figures, proceedings of Hard Probes 2006 International Conference

Published
2007
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13. Low Mass Dimuon Production in Indium-Indium Collisions at the CERN SPS

Author

NA60 Collaboration, Floris, M., Arnaldi, R., Averbeck, R., Banicz, K., Castor, J., Chaurand, B., Cicalo, C., Colla, A., Cortese, P., Damjanovic, S., David, A., de Falco, A., Devaux, A., Dress, A., Ducroux, L., Farjeix, J., En'yo, H., Ferretti, A., Förster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J., Keil, M., Kluberg, L., Lozano, J., Lourenço, C., Manso, F., Masoni, A., Martins, P., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., 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 Wöhri, H. K.

Subjects
Nuclear Experiment
Abstract

NA60 is a fixed-target experiment at the CERN SPS which measured dimuon production in nucleus-nucleus and proton-nucleus collisions. In this paper we report on a precision measurement of low-mass muon pairs in 158 AGeV indium-indium collisions. A significant excess of pairs is observed above the yield expected from neutral meson decays. The excess can be isolated by subtraction of expected sources, thanks to the excellent mass resolution and large sample size., Comment: 4 pages, 3 figures, Contribution at XLIst Rencontres de Moriond, "QCD and High Energy Hadronic Interactions"

Published
2006

14. Nuclear dependence of light neutral meson production in p–A collisions at 400 GeV with NA60

Author

Pierre Jarron, H. J. Specht, P. Rosinsky, R. Arnaldi, P. Ramalhete, A. Devaux, J. Seixas, J. Lozano, B. Chaurand, T. Poghosyan, Raphael Noel Tieulent, A. Neves, P. Force, G. Puddu, Hiroaki Ohnishi, H. En'yo, A. Uras, Sergio Serci, A. Colla, Enrico Scomparin, P. Parracho, N. Guettet, Alessandro Ferretti, P. Martins, K. Borer, Giulio Usai, Laurent Ducroux, R. Veenhof, J. Fargeix, C. Oppedisano, Michele Floris, R. Shahoyan, Wen-Chang Chen, S. Damjanovic, P. Pillot, A. Masoni, J. M. Heuser, P. Sonderegger, H. K. Wöhri, A. Förster, E. Radermacher, Z. Li, M. Keil, J. Castor, A. Guichard, L. Kluberg, C. Lourenço, Pietro Cortese, Corrado Cicalo, A. De Falco, H. Gulkanian, Franck Manso, K. Banicz, A. David, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-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)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
NA60, Particle physics, Physics and Astronomy (miscellaneous), Meson, Proton, Nuclear Theory, FOS: Physical sciences, cross section: ratio, lcsh:Astrophysics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Power law, omega(783): decay, Computer Science::Digital Libraries, Spectral line, High Energy Physics - Experiment, transverse momentum: momentum spectrum, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, lcsh:QB460-466, Nuclear Physics - Experiment, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, meson: production, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Engineering (miscellaneous), p nucleus: scattering, Physics, Muon, 010308 nuclear & particles physics, Sigma, dimuon: mass spectrum, p: beam, CERN SPS, eta(958): decay, muon: pair production, Pair production, lcsh:QC770-798, Production (computer science), High Energy Physics::Experiment, Phi(1020): decay
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 proton beam at the CERN SPS. The transverse momentum spectra of the $$\rho /\omega $$ ρ/ω and $$\phi $$ ϕ mesons are measured in the full $$p_{\mathrm {T}}$$ pT range accessible, from $$p_{\mathrm {T}}= 0$$ pT=0 up to $$2 \, {\hbox {GeV/c}}$$ 2GeV/c . The nuclear dependence of the production cross sections of the $$\eta $$ η , $$\omega $$ ω and $$\phi $$ ϕ mesons has been found to be consistent with the power law $$\sigma _{\mathrm {pA}} \propto {\mathrm {A}}^\alpha $$ σpA∝Aα , with the $$\alpha $$ α parameter increasing as a function of $$p_{\mathrm {T}}$$ pT for all the particles, and an approximate hierarchy $$\alpha _\eta \approx \alpha _\phi > \alpha _\omega $$ αη≈αϕ>αω . The cross section ratios $$\sigma _\eta /\sigma _\omega $$ ση/σω , $$\sigma _\rho /\sigma _\omega $$ σρ/σω and $$\sigma _\phi /\sigma _\omega $$ σϕ/σω have been studied as a function of the size A of the production target, and an increase of the $$\eta $$ η and $$\phi $$ ϕ yields relative to the $$\omega $$ ω is observed from p–Be to p–U collisions.

Published
2019

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

Author

H.K. Wöhri, Z. Li, Enrico Scomparin, B. Chaurand, J. Seixas, Alberto Masoni, P. Ramalhete, P. Pillot, P. Force, P. Rosinsky, H. Enʼyo, A. De Falco, J. Lozano, S. Serci, P. Parracho, S. Damjanovic, A. Colla, Alessandro Ferretti, A. Guichard, H. J. Specht, Wen-Chang Chen, Michele Floris, Laurent Ducroux, G. Puddu, A. Devaux, J. M. Heuser, Chiara Oppedisano, Raphael Noel Tieulent, Hiroaki Ohnishi, A. Förster, A. David, Ruben Shahoyan, G. L. Usai, E. Radermacher, N. Guettet, K. Banicz, A. Uras, J. Fargeix, A. Neves, H. Gulkanian, P. Sonderegger, P. Martins, Franck Manso, J. Castor, M. Keil, Roberta Arnaldi, Rob Veenhof, Pietro Cortese, C. Cicalo, Carlos Lourenco, and T. Poghosyan

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson production, Large Hadron Collider, 010308 nuclear & particles physics, Nuclear Theory, Hadron, Inverse, 01 natural sciences, Spectral line, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics
Abstract

The NA60 experiment at the CERN SPS has studied ϕ meson production in In–In collisions at 158 A GeV via both the K + K − and the μ + μ − 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

16. Evidence for the production of thermal muon pairs with masses above 1 GeV/c 2 in 158 A GeV indium-indium collisions

Author

Roberta Arnaldi, Franck Manso, N. Guettet, H. Gulkanian, Z. Li, T. Poghosyan, K. Banicz, J. Fargeix, P. Pillot, Raphael Noel Tieulent, A. Guichard, C. Cicalo, A. Förster, A. David, Ruben Shahoyan, A. Neves, P. Ramalhete, P. Martins, Hiroaki Ohnishi, Wen-Chang Chen, Alberto Masoni, G. Puddu, Michele Floris, S. Damjanovic, Chiara Oppedisano, S. Serci, A. Devaux, K. Borer, Laurent Ducroux, G. L. Usai, Rob Veenhof, H. J. Specht, A. Colla, B. Chaurand, Markus Keil, J. Castor, Alessandro Ferretti, Pietro Cortese, A. De Falco, Carlos Lourenco, L. Kluberg, Joao Seixas, Enrico Scomparin, P. Parracho, J. Lozano, Hermine Katharina Wöhri, P. Rosinsky, E. Radermacher, J. M. Heuser, P. Force, H. En'yo, and P. Sonderegger

Subjects
Physics, Muon, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Nuclear Theory, chemistry.chemical_element, 01 natural sciences, 7. Clean energy, Nuclear physics, chemistry, Yield (chemistry), 0103 physical sciences, D meson, Thermal, Transverse mass, High Energy Physics::Experiment, Invariant mass, Nuclear Experiment, 010306 general physics, Nucleon, Engineering (miscellaneous), Indium
Abstract

The yield of muon pairs in the invariant mass region 1

Published
2009

17. The production of $\rho$ , $\omega$ and $\phi$ vector-mesons by protons and sulphur ions with incident momentum of 200 GeV/c per nucleon

Author

J. Castor, X. Tarrago, P. Bordalo, A. Romana, J.-R. Pizzi, Brigitte Cheynis, A. Baldit, A. Devaux, O. Drapier, B. Chaurand, R. Ferreira, G. Borges, M.C. Abreu, C. Gerschel, J. Astruc, Bruno Espagnon, Ruben Shahoyan, J. Guimaraes, Helena Santos, S. Ramos, C. Baglin, I. Chevrot, C. Quintans, R. Haroutunian, P. Force, Carlos Lourenco, L. Kluberg, J.-Y. Grossiord, M. Bedjidian, A. Bussiere, P. Saturnini, S. Mourgues, P. Petiau, P. Sonderegger, D. Jouan, A. Guichard, and J. Fargeix

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, Sigma, 01 natural sciences, 7. Clean energy, Omega, Spectral line, Nuclear physics, Momentum, 0103 physical sciences, Transverse mass, Production (computer science), Nuclear Experiment, 010306 general physics, Nucleon, Engineering (miscellaneous)
Abstract

The production of $\rho$ , $\omega$ and $\phi$ vector-mesons, detected through their $\mu\mu$ decay channel, is studied in p-W, S-S, S-Cu and S-U reactions at 200 GeV/c per nucleon incident momentum. Their inclusive cross-sections are determined in various transverse momentum intervals and their dependence on the projectile and target mass numbers is investigated. The relative yield $B_{\mu\mu}\sigma_{\phi}/(B_{\mu\mu}\sigma_{\rho} + B_{\mu\mu}\sigma_{\omega})$ is measured, both as a function of the transverse momentum, pT, and of the collision centrality. While this ratio exhibits no significant dependence with pT, it clearly increases with the centrality of the collision. Effective temperatures deduced from the transverse mass spectra, $d\sigma/dM_T$ , lead to values of $T_{\rho + \omega}$ equal or slightly higher than $T_{\phi}$ . Both these effective temperatures smoothly increase from p-W to S-U reactions.

Published
2005

18. First results of the NA60 experiment at the CERN SPS

Author

J. Seixas, A. David, Markus Keil, S. Damjanović, Brigitte Cheynis, Jean-Yves Grossiord, Raphael Noel Tieulent, N. Guettet, R. Shahoyan, Laurent Ducroux, Jan Buytaert, P. Force, R. Veenhof, N. De Marco, Chiara Oppedisano, A. Colla, E. Radermacher, Franck Manso, H. En'yo, Wen-Chang Chen, P. Pillot, K. Banicz, Hermine Katharina Wöhri, Alessandro Ferretti, P. Rosinsky, H. J. Specht, A. Neves, B. Chaurand, J. Lozano, Pietro Cortese, Hiroaki Ohnishi, S. Serci, Enrico Scomparin, A. Devaux, A. Drees, J. Castor, G. L. Usai, H. Gulkanian, P. Sonderegger, Z. Li, Carlos Lourenco, Pcf Parracho, L. Kluberg, J. M. Heuser, E. Tveiten, Corrado Cicalo, H. Vardanyan, A. Guichard, K. Borer, P. Ramalhete, Roberta Arnaldi, A. De Falco, A.A. Grigorian, 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), 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), 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), D. Adamova, A. Kugler, P. Tlusty, NA60, 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), 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)-Université Claude Bernard Lyon 1 (UCBL), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Large Hadron Collider, Muon, Meson production, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Nuclear Theory, 7. Clean energy, 01 natural sciences, Vertex (geometry), law.invention, Nuclear physics, Telescope, Muon spectrometer, law, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Physics::Accelerator Physics, High Energy Physics::Experiment, Heavy ion, Nuclear Experiment, 010306 general physics
Abstract

NA60; The NA60 experiment at the CERN SPS studies dimuon production in proton and heavy ion collisions. Its silicon pixel vertex telescope allows tracking of muon pairs in the vertex region, complementing the information from the muon spectrometer, and improving the mass resolution and signal-to-noise ratio. First results from the In-In data taking are shown for the light resonances and the J/$\psi$ meson production.

Published
2005

19. Charged particle multiplicity in Pb-Pb collisions from the NA50 experiment

Author

R. Haroutunian, Roberta Arnaldi, Sanda Dita, D. Jouan, C. Quintans, M. Atayan, G. Borges, T. Claudino, T.L. Karavitcheva, B. Espagnon, P. Petiau, A. Baldit, Paolo Giubellino, Pietro Cortese, Stefania Beole, Enrico Scomparin, Y.K. Gavrilov, M. Gonin, Serban Constantinescu, X. Tarrago, P. Sonderegger, Mario Sitta, C. Castanier, P. Force, Marek Idzik, O. Drapier, H.R. Gulkanyan, F.F. Guber, Alexey Kurepin, Carlos Lourenco, L. Kluberg, N.S. Topilskaya, P. Saturnini, M. Mac Cormick, Mauro Gallio, V. Boldea, L. Riccati, A. Musso, G. L. Usai, C. Baglin, P. Rato Mendes, S. Serci, Ermanno Vercellin, Luciano Ramello, G. Puddu, J.-R. Pizzi, Bruno Alessandro, B. Chaurand, L. Capelli, N. Willis, A. Devaux, C. Gerschel, F Prino, W.L. Prado da Silva, F. Sigaudo, J.-Y. Grossiord, A. Piccotti, T. Wu, A. Bussiere, M. P. Comets, Enrico Scalas, A. Defalco, A.A. Grigorian, G. Dellacasa, Alberto Masoni, A. Romana, João Cruz, P. Macciotta, Calin Alexa, Helena Santos, M.B. Golubeva, M. Bedjidian, A. Guichard, F. Prino, S. Grigorian, J. Fargeix, A. Marzari-Chiesa, Massimo Masera, P. Bordalo, S. Ramos, R Hokobyan, Brigitte Cheynis, E. Chiavassa, Ruben Shahoyan, N DeMarco, Marco Monteno, Y. Le Bornec, J. Castor, S. Borenstein, L. Villatte, Corrado Cicalo, Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), 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), 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), 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 d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), NA50, Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-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), 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)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, History, Large Hadron Collider, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Nuclear Theory, 01 natural sciences, 7. Clean energy, Charged particle, Computer Science Applications, Education, Nuclear physics, Transverse plane, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], 0103 physical sciences, Impact parameter, Multiplicity (chemistry), Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon, Particle density, Charged particle beam
Abstract

NA50; Angular distributions of charged particles produced in Pb-Pb collisions at the CERN SPS have been measured by the NA50 experiment. Measurements have been performed with a silicon microstrip detector at two different beam energies (40 and 158 GeV/nucleon) and over a wide impact parameter (centrality) range. The centrality of the collision has been evaluated both by neutral transverse energy released in the interaction and by spectator nucleons energy (zero degree energy). The charged particle density at midrapidity shows a linear dependence on the number of participating nucleons at both beam energies. The particle density per participant pair and its $\sqrt{S}$ dependence are also studied.

Published
2005

20. First results and future perspectives of the NA60 experiment

Author

C Oppedisano, (for the NA60 Collaboration), R Arnaldi, K Banicz, K Borer, J Buytaert, J Castor, B Chaurand, W Chen, B Cheynis, C Cicalo, A Colla, P Cortese, A David, A de Falco, N de Marco, A Devaux, A Drees, L Ducroux, H En'yo, A Ferretti, M Floris, P Force, A Grigorian, J-Y Grossiord, N Guettet, A Guichard, H Gulkanian, J Heuser, M Keil, L Kluberg, Z Li, C Lourenço, J Lozano, F Manso, A Masoni, A Neves, H Ohnishi, G Puddu, E Radermacher, P Rosinsky, E Scomparin, J Seixas, S Serci, R Shahoyan, P Sonderegger, G Usai, H Vardanyan, and H Wöhri

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Large Hadron Collider, Meson, Spectrometer, Physics::Instrumentation and Detectors, Particle identification, Charged particle, Nuclear physics, Pseudorapidity, High Energy Physics::Experiment, Nuclear Experiment, Lepton
Abstract

The NA60 experiment at the CERN SPS studies the production of open charm and prompt dimuons in collisions induced by proton and heavy ion beams on nuclear targets. The experimental setup includes a silicon vertex telescope, placed inside a dipole magnetic field, to match charged particle tracks with the muon tracks measured by a muon spectrometer. In p-A collisions the vertex telescope is mostly made of silicon microstrip planes, whereas in A-A interactions the higher multiplicity imposes the use of high granularity silicon pixel detectors. The high interaction rate required for the study of rare processes imposes the use of radiation tolerant pixel detectors. NA60 took its first data in the year 2002, with 400 GeV protons and with Pb ions of 20 and 30 GeV per nucleon. The proton data have been used for the study of dimuon production, while the heavy ion data were devoted to the commissioning of the pixel detectors and to the study of charged particle pseudorapidity densities. After an overview of the detector concept, this paper presents the first results obtained with the 2002 data.

Published
2003

21. Pseudorapidity distributions of charged particles in Pb-Pb collisions at super proton synchrotron energies from the NA50 experiment

Author

T. Claudino, J.-Y. Grossiord, Mario Sitta, Paolo Giubellino, Y.K. Gavrilov, Sergio Serci, M. Idzik, B. Espagnon, X. Tarrago, C. Castanier, Bruno Alessandro, Alexey Kurepin, A. Piccotti, G. Dellacasa, A. Baldit, Serban Constantinescu, Helena Santos, M. Masera, M. P. Comets, F. Prino, M. Mac Cormick, L. Villatte, Roberta Arnaldi, A.A. Grigorian, L. Riccati, A. Romana, Corrado Cicalo, I. Chevrot, A. De Falco, P. Bordalo, R. Hakobyan, J. Fargeix, Ermanno Vercellin, A. Bussiere, N. De Marco, S. Ramos, Stefania Beole, P. Saturnini, W.L. Prado da Silva, Calin Alexa, F. Sigaudo, O. Drapier, R. Haroutunian, M. C. Abreu, Giulio Usai, N. Willis, A. Masoni, M.B. Golubeva, A. Devaux, P. Force, G. Puddu, A. Guichard, C. Quintans, N. Constans, M. Atayan, Enrico Scalas, S. Silva, M. Bedjidian, Brigitte Cheynis, Pietro Cortese, E. Scomparin, G. Borges, T.L. Karavitcheva, S. Grigorian, P. Petiau, Carlos Lourenco, L. Kluberg, N.S. Topilskaya, P. Sonderegger, J.-R. Pizzi, Y. Le Bornee, Marek Idzik, A. Musso, Sanda Dita, D. Jouan, M. Gonin, H.R. Gulkanyan, Mauro Gallio, V. Boldea, L. Capelli, F.F. Guber, Luciano Ramello, P. Rato Mendes, B. Chaurand, C. Gerschel, Laurent Ducroux, C. Baglin, P. Macciotta, E. Chiavassa, Ruben Shahoyan, A. Marzari-Chiesa, Marco Monteno, and J. Castor

Subjects
Physics, Particle physics, Large Hadron Collider, Nuclear Theory, General Physics and Astronomy, Super Proton Synchrotron, Charged particle, Nuclear physics, Pseudorapidity, High Energy Physics::Experiment, Multiplicity (chemistry), Impact parameter, Nuclear Experiment, Nucleon
Abstract

We present the measurements of charged particle pseudorapidity distributions dNch/dη performed by the NA50 experiment in Pb-Pb collisions at the CERN SPS. Measurements were done at incident energies of 40 GeV (√s = 8.77 GeV) and 158 GeV (√s = 17.3 GeV) per nucleon over a broad impact parameter range. The multiplicity distributions are studied as a function of centrality using the number of participating nucleons(N part ), or the number of binary nucleon-nucleon collisions (Ncoll). Their values at midrapidity exhibit a linear scaling withN part at both energies. Particle yield increases approximately by a factor of 2 betweeny √s = 8.77 GeV and √s = 17.3 GeV.

Published
2003

22. $\phi$ and $\rho$ $plus$ $\omega$ vector-mesons produced in lead-induced collisions

Author

P. Rato Mendes, B. Chaurand, S R Borenstein, Mauro Gallio, V. Boldea, C. Gerschel, Mario Sitta, H.R. Gulkanyan, J. Fargeix, Sergio Serci, M. P. Comets, A. Masoni, Ermanno Vercellin, Enrico Scomparin, M. Gonin, S. Ramos, A. Baldit, A. Romana, Y Le Bornec, Calin Alexa, L. Ramello, W.L. Prado da Silva, P. Petiau, Roberta Arnaldi, F. Sigaudo, G. Puddu, P. Sonderegger, Paolo Giubellino, Bruno Alessandro, L. Riccati, N. De Marco, E Scalas, A. De Falco, Sanda Dita, D. Jouan, C Castanier, A. Bussiere, G. Borges, M.C. Abreu, C. Quintans, A. Guichard, T.L. Karavitcheva, M. Atayan, P. Saturnini, Serban Constantinescu, N. Constans, Y.K. Gavrilov, B. Espagnon, M.B. Golubeva, A. Piccotti, J.-R. Pizzi, Alexey Kurepin, A.A. Grigorian, L. Villatte, João Cruz, S. Silva, F. Prino, Jean-Yves Grossiord, M Bedjidian, N. Willis, L Capelli, G. L. Usai, A. Musso, Brigitte Cheynis, Pietro Cortese, Carlos Lourenco, L. Kluberg, N.S. Topilskaya, Stefania Beole, A. Marzari-Chiesa, Marco Monteno, P. Force, M. Mac Cormick, J. Castor, Corrado Cicalo, S. Grigorian, X. Tarrago, T. Claudino, Massimo Masera, E. Chiavassa, Ruben Shahoyan, C. Baglin, R Haroutunian, G. Dellacasa, Helena Santos, P. Macciotta, O Drapier, P. Bordalo, R. Hakobyan, A. Devaux, Marek Idzik, and F.F. Guber

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Proton, Meson, Strangeness production, Inverse, Heavy ion, Nuclear Experiment, Omega, Scaling, Ion
Abstract

The experiment NA50 studies the strangeness production by means of the BRμμσ/(BRρμμσρ + BRωμμσω) cross-sections ratio in relativistic heavy ion collisions with respect to proton and light ion collisions. New results for Pb+Pb interactions at 158 A GeV/c are presented (1998 data) and analysed with a different method. The BRμμσ/(BRρμμσρ + BRωμμσω) ratio shows an increase with the number of participants, in agreement with previous results. The inverse slope parameter extracted from the MT universal scaling is also studied.

Published
2002

23. Production of ϱ + ω and Φ in p-W and SU collisions at 200 GeV/nucleon

Author

B. Espagnon, C. Baglin, A. Romana, M.C. Abreu, S. Papillon, G. Landaud, Ph. Gorodetzky, S. Silva, J. Castor, X. Tarrago, A. Guichard, B. Chaurand, Joao Varela, O. Drapier, M. Bedjidian, C. Gerschel, R. Kossakowski, C. Racca, D. Jouan, S. Ramos, A. Baldit, A. Bussière, R. Ferreira, E. Descroix, P. Force, J. Fargeix, P. Sonderegger, J.-R. Pizzi, J.M. Gago, Didier Contardo, Luis Peralta, Carlos Lourenco, L. Kluberg, T. Chambon, Rachid Mazini, A. Baldisseri, P. Liaud, P. Bordalo, A. Devaux, J.-Y. Grossiord, J. P. Guillaud, and R. Haroutunian

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Transverse momentum, Energy density, Transverse mass, Rapidity, Nuclear Experiment, Nucleon
Abstract

The transverse mass differential cross-sections for the ϱ + ω and Φ resonances is obtained, in the central rapidity region, in p - W and S  U interactions at 200 GeV/nucleon. The measured ϱ + ω and Φ temperatures are ∼ 15% higher in S  U as compared to p - W collisions. The ratio of cross-sections times branching ratios into the dimuon channel B Φ σ Φ (B ϱ σ ϱ + B ω σ ω ) is studied as a function of the energy density reached in the collision and of the dimuon transverse momentum. The measured ratio is 2 to 3 times larger in S  U than in p - W collisions and an enhancement is observed in S  U interactions with increasing energy density.

Published
1996

24. New results on J/ψ from the NA50 experiment

Author

A. Piccotti, João Cruz, Roberta Arnaldi, J.-R. Pizzi, F. Prino, A. Bussiere, Ermanno Vercellin, Paolo Giubellino, H.R. Gulkanyan, Helena Santos, M. Mac Cormick, P. Petiau, A. Marzari-Chiesa, W.L. Prado da Silva, F. Sigaudo, F.F. Guber, Y.K. Gavrilov, N. Willis, S. Ramos, O. Drapier, P. Sonderegger, G. Puddu, Luciano Ramello, A. Devaux, M.B. Golubeva, Enrico Scalas, G. L. Usai, Alexey Kurepin, G. Dellacasa, Alberto Masoni, Sanda Dita, D. Jouan, P. Rato Mendes, S. Serci, C. Quintans, M. Atayan, N. De Marco, T. Claudino, B. Chaurand, X. Tarrago, A. Romana, C. Gerschel, Pietro Cortese, Calin Alexa, M. Bedjidian, C. Castanier, Brigitte Cheynis, S. Grigorian, Mauro Gallio, Carlos Lourenco, P. Bordalo, R. Hakobyan, V. Boldea, Enrico Scomparin, L. Kluberg, N.S. Topilskaya, A. De Falco, J.-Y. Grossiord, A. Guichard, Stefania Beole, T. Wu, M. Gonin, L. Capelli, A. Musso, P. Force, Mario Sitta, Marek Idzik, P. Saturnini, J. Fargeix, C. Baglin, P. Macciotta, Massimo Masera, E. Chiavassa, Ruben Shahoyan, M. P. Comets, B. Espagnon, R. Haroutunian, G. Borges, T.L. Karavitcheva, Corrado Cicalo, Marco Monteno, Y. Le Bornec, L. Riccati, J. Castor, S. Borenstein, L. Villatte, A. Baldit, Serban Constantinescu, Bruno Alessandro, and A.A. Grigorian

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Nuclear Theory, Plasma, 01 natural sciences, Atomic and Molecular Physics, and Optics, Charged particle, Ion, Renormalization, Nuclear physics, 0103 physical sciences, Quark–gluon plasma, High Energy Physics::Experiment, Heavy ion, Nuclear Experiment, 010306 general physics
Abstract

The NA50 experiment studies the production of J/γ in Pb+Pb collisions. The anomalous J/ψ suppression in relativistic heavy ion collisions, considered an unambiguous signature for the formation of a quark gluon plasma, is studied in the dimuon channel, using as reference the Drell-Yan muon pairs. Preliminary results from the analysis of the 2000 data, with the target region vacuum, are presented and compared to an update of those obtained from previous data samples.

Published
2003

25. ψ′ and muon pair production in p-W and S-U collisions

Author

F. Malek, Joao Varela, C. Racca, Bruno Espagnon, P. Sonderegger, L. Luquin, B. Ronceux, G. Landaud, Ph. Gorodetzky, X. Tarrago, C. Baglin, P. Liaud, C. Barriere, A. Baldit, J.-R. Pizzi, E. Descroix, P. Bordalo, R. Kossakowski, S. Ramos, A. Devaux, S. Silva, R. Haroutunian, M.C. Abreu, R.A. Salmeron, J. Castor, B. Grosdidier, J.M. Gago, T. Chambon, R. Ferreira, O. Drapier, A. Guichard, Francois Vazeille, J. Fargeix, A. Romana, R. Mandry, L. Fredj, Luis Peralta, J.-Y. Grossiord, Carlos Lourenco, L. Kluberg, Didier Contardo, Rachid Mazini, J.P. Guillaud, A. Bussiere, D. Jouan, D. Lazic, B. Chaurand, C. Gerschel, M. Bedjidian, and P. Force

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Meson, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Nuclear Theory, Hadron, Quarkonium, 01 natural sciences, Nuclear physics, Particle decay, Pair production, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Nucleon, Lepton
Abstract

In this paper we present a study on the production of the J ψ and ψ′ resonances, decaying into muon pairs, in S-U collisions, at 200 GeV per incident nucleon. We find that the ratio between ψ′ and tJ ψ yields decreases as E T , the neutral transverse energy produced in the collision, increases. There is also a clear decrease of this ratio when going from p-W to S-U interactions. Assuming the high mass continuum to be Drell-Yan we discuss the possible understanding of the intermediate dimuon mass region as a superposition of Drell-Yan (extrapolated down in mass) and muon pairs from the semileptonic decays of charmed mesons. The p-W data is found to be explained by this procedure. However, the S-U data seems to be incompatible with a linear extrapolation from the proton-nucleus results.

Published
1994

26. Measurement of dielectron production in niobium-niobium collisions at 1.05 GeV/nucleon

Author

Robert C. Welsh, G. F. Krebs, P. N. Kirk, G. Igo, A. Yegneswaran, P. Force, A. Letessier-Selvon, J. Gordon, L. Madansky, J. B. Carroll, Z. F. Wang, C. Naudet, S. Beedoe, H. S. Matis, G. Roche, L. S. Schroeder, Peter A. Seidl, D. H. Miller, and T. J. Hallman

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Particle physics, Niobium, chemistry.chemical_element, Kinetic energy, Nuclear physics, Pair production, chemistry, High Energy Physics::Experiment, Production (computer science), Invariant mass, Nuclear Experiment, Nucleon, Lepton
Abstract

A dielectron signal for pair masses greater than ${\mathit{M}}_{\mathrm{\ensuremath{\pi}}}$ is observed in Nb+Nb collisions at 1.05 GeV/nucleon beam kinetic energy. The invariant mass spectrum and the associated multiplicity distribution are presented. Comparisons are made with previous cross section measurements in p+Be and Ca+Ca.

Published
1993

27. Meson production inp+U, O+U and S+U interactions at 200 GeV/nucleon

Author

F. Staley, E. Descroix, A. Bussiere, C. Racca, P. Liaud, Philippe Busson, R.A. Salmeron, S. Ramos, M.C. Abreu, A. Baldit, S. Silva, A. Guichard, J. Castor, A. Baldisseri, Carlos Lourenco, L. Kluberg, J. P. Guillaud, R. Ferreira, D. Jouan, J.M. Gago, O. Drapier, C. Baglin, Ph. Gorodetzky, R. Kossakowski, Francois Vazeille, R. Cases, R. Haroutunian, G. Landaud, Claude Charlot, P. Bordalo, C. Barriere, M. Bedjidian, J. Fargeix, A. Devaux, J.-R. Pizzi, B. Chaurand, C. Gerschel, Luis Peralta, Didier Contardo, P. Force, T. Chambon, J.-Y. Grossiord, X. Felgeyrolles, Joao Varela, X. Tarrago, A. Romana, P. Sonderegger, L. Fredj, S. Papillon, and B. Grosdidier

Subjects
Physics, Nuclear reaction, Particle physics, Physics and Astronomy (miscellaneous), Proton, Meson, Nuclear Theory, Hadron, Elementary particle, Nuclear physics, Pion, Nuclear Experiment, Nucleon, Engineering (miscellaneous), Boson
Abstract

Meson production in proton, oxygen and sulphur interactions with uranium targets at 200 GeV/nucleon is studied. We measure the inclusive meson cross-section d σ/dPT2 and its evolution fromp+U to S+U. The cross-section fitted with an exponential gives an inverse slopePT0 of the order of 210 MeV/c. As a function of the neutral transverse energy,PT0 values show a slight rise followed by a plateau. The normalized difference (σ+−σ−)/σ− between positive and negative meson cross-sections is found to increase withET.

Published
1992

28. Muon pair production in heavy ion interactions at 200 GeV per nucleon

Author

A. Bussiere, B. Chaurand, J.-R. Pizzi, R. Haroutunian, C. Gerschel, G. Landaud, A. Baldisseri, P. Liaud, J.-Y. Grossiord, X. Tarrago, M. Bedjidian, B. Grosdidier, A. Baldit, Carlos Lourenco, Didier Contardo, L. Kluberg, J.P. Guillaud, X. Felgeyrolles, P. Sonderegger, F. Staley, J. Castor, D. Jouan, Ph. Gorodetzky, R. Kossakowski, P. Bordalo, P. Force, Luis Peralta, S. Papillon, P. Busson, C. Racca, A. Devaux, A. Descroix, T. Chambon, S. Ramos, A. Romana, Claude Charlot, R.A. Salmeron, A. Guichard, O. Drapier, J.M. Gago, M.C. Abreu, Joao Varela, J. Fargeix, S. Silva, C. Baglin, L. Fredj, R. Ferreira, Francois Vazeille, and R. Cases

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, Muon, Quarkonium, Nuclear physics, Particle decay, Pair production, Effective mass (solid-state physics), High Energy Physics::Experiment, Atomic physics, Nuclear Experiment, Nucleon, Lepton
Abstract

The NA38 experiment measures muon pair production in 200 GeV per nucleon nucleus-nucleus interactions at the CERN SPS. Dimuon production is studied as a function of the neutral transverse energy produced in the collisions, which reflects the energy density reached in the interaction. The J / ψ yield relative to muon pairs in the mass continuum decreases with increasing energy density. The atomic number dependence of the cross sections has been studied using the parametrization σ ∞ ( A proj . A targ . ) α which leads to α = 0.91 ± 0.04 for the J / ψ , and α = 1.01 ± 0.04 for muon pairs in the mass range [1.7, 2.7] GeV/c 2 . The study of dimuon transverse momentum distributions shows an enhancement of the J / ψ suppression for low P T values. The average values 〈P T 〉 and 〈P T 2 〉 increase with increasing transverse energy in case of the J / ψ , and are rather flat for muon pairs in the mass continuum. Such a behaviour is expected in case of quark-gluon plasma formation. However, a model based on parton multiple scattering in the initial state leads to a variation of 〈P T 2 〉 as a function of the mean thickness of nuclear matter encountered by the partons, which seems also to account for the observed effect. In addition, low mass dimuons are studied. An enhancement of the φ /( ϱ + ω ) ratio is observed with increasing energy density.

Published
1992

29. phi production in In–In collisions at 158 A GeV

Author

G. Puddu, J. Lozano, H. J. Specht, A. Guichard, Enrico Scomparin, B. Chaurand, Franck Manso, H.R. Gulkanyan, A. Colla, J. M. Heuser, Alessandro Ferretti, P. Rosinsky, Hiroaki Ohnishi, S. Serci, K. Borer, G. L. Usai, Alberto Masoni, Laurent Ducroux, K. Banicz, Z. Li, A. Uras, P. Force, J. Castor, E. Radermacher, P. Parracho, H. K. Wöhri, A. Förster, J. Fargeix, P. Ramalhete, T. Poghosyan, C. Cicalo, Raphael Noel Tieulent, Philippe Pillot, A. De Falco, S. Damjanovic, P. Martins, Wen-Chang Chen, A. David, A. Neves, A. Devaux, R. Veenhof, M. Keil, Roberta Arnaldi, N. Guettet, H. En'yo, Pietro Cortese, Carlos Lourenco, J. Seixas, P. Sonderegger, Ruben Shahoyan, Michele Floris, Chiara Oppedisano, 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
Physics, Nuclear and High Energy Physics, Particle physics, Large Hadron Collider, Muon, 010308 nuclear & particles physics, Physics::Instrumentation and Detectors, Nuclear Theory, Strangeness, 01 natural sciences, Spectral line, Nuclear physics, 0103 physical sciences, Quark–gluon plasma, Mass spectrum, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Transverse mass, High Energy Physics::Experiment, 010306 general physics, Nucleon, Nuclear Experiment
Abstract

International audience; The NA60 experiment at the CERN SPS studied phi production in In–In collisions at 158 A GeV via muon and kaon decay channels. The yields and transverse mass spectra observed in the two channels are compatible within errors. The results are compared to the previous measurements in Pb–Pb collisions, where large discrepancies were observed between NA50 (muon pairs) and NA49 (kaon pairs).

Published
2009

30. J/psi azimuthal anisotropy relative to the reaction plane in Pb-Pb collisions at 158 GeV per nucleon

Author

F. Prino, B. Alessandro, C. Alexa, R. Arnaldi, M. Atayan, S. Beolè, V. Boldea, P. Bordalo, G. Borges, C. Castanier, J. Castor, B. Chaurand, B. Cheynis, E. Chiavassa, C. Cicalò, M. P. Comets, S. Constantinescu, P. Cortese, A. De Falco, N. De Marco, G. Dellacasa, A. Devaux, S. Dita, J. Fargeix, P. Force, M. Gallio, C. Gerschel, P. Giubellino, M. B. Golubeva, A. A. Grigoryan, S. Grigoryan, F. F. Guber, A. Guichard, H. Gulkanyan, M. Idzik, D. Jouan, T. L. Karavicheva, L. Kluberg, A. B. Kurepin, Y. Le Bornec, C. Lourenço, M. Mac Cormick, A. Marzari-Chiesa, M. Masera, A. Masoni, M. Monteno, A. Musso, P. Petiau, A. Piccotti, J. R. Pizzi, G. Puddu, C. Quintans, L. Ramello, S. Ramos, L. Riccati, H. Santos, P. Saturnini, E. Scomparin, S. Serci, R. Shahoyan, F. Sigaudo, M. Sitta, P. Sonderegger, X. Tarrago, N. S. Topilskaya, G. L. Usai, E. Vercellin, L. Villatte, N. Willis, T. Wu, 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), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), NA50, 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), 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), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Meson, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Theoretical models, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucl-ex, 01 natural sciences, Dissociation (chemistry), Azimuth, Nuclear physics, Transverse plane, 0103 physical sciences, Nuclear Physics - Experiment, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), 010306 general physics, Nucleon, Anisotropy, Nuclear Experiment, Fourier series, Engineering (miscellaneous)
Abstract

The J/$\psi$ azimuthal distribution relative to the reaction plane has been measured by the NA50 experiment in Pb-Pb collisions at 158 GeV/nucleon. Various physical mechanisms related to charmonium dissociation in the medium created in the heavy ion collision are expected to introduce an anisotropy in the azimuthal distribution of the observed J/$\psi$ mesons at SPS energies. Hence, the measurement of J/$\psi$ elliptic anisotropy, quantified by the Fourier coefficient v$_2$ of the J/$\psi$ azimuthal distribution relative to the reaction plane, is an important tool to constrain theoretical models aimed at explaining the anomalous J/$\psi$ suppression observed in Pb-Pb collisions. We present the measured J/$\psi$ yields in different bins of azimuthal angle relative to the reaction plane, as well as the resulting values of the Fourier coefficient v$_{2}$ as a function of the collision centrality and of the J/$\psi$ transverse momentum. The reaction plane has been estimated from the azimuthal distribution of the neutral transverse energy detected in an electromagnetic calorimeter. The analysis has been performed on a data sample of about 100 000 events, distributed in five centrality or p$_{\rm T}$ sub-samples. The extracted v$_{2}$ values are significantly larger than zero for non-central collisions and are seen to increase with p$_{\rm T}$., Comment: proceedings of HP08 conference corrected a typo in one equation

Published
2009
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31. φ, ϱ, and ω production in pU, OU and SU reactions at 200 GeV per nucleon

Author

Ph. Gorodetzky, B. Grosdidier, R. Ferreira, R. Kossakowski, G. Landaud, L. Fredj, S. Papillon, Francois Vazeille, A. Romana, R. Cases, Claude Charlot, E. Descroix, P. Bordalo, S. Ramos, M.C. Abreu, A. Baldit, X. Tarrago, F. Staley, A. Devaux, Philippe Busson, S. Silva, J. Castor, A. Guichard, P. Liaud, Luis Peralta, T. Chambon, P. Sonderegger, J. Fargeix, A. Baldisseri, D. Jouan, M. Bedjidian, C. Racca, R. Haroutunian, Joao Varela, A. Bussière, O. Drapier, Didier Contardo, C. Baglin, J.M. Gago, Carlos Lourenco, L. Kluberg, J.-R. Pizzi, X. Felgeyrolles, J.-Y. Grossiord, B. Chaurand, C. Gerschel, J. P. Guillaud, and P. Force

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, 010308 nuclear & particles physics, Nuclear Theory, Hadron, Continuum (design consultancy), 7. Clean energy, 01 natural sciences, Ion, Nuclear physics, Pair production, Yield (chemistry), 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Nucleon, Low Mass
Abstract

Low mass muon pair production at high P T and low X F studied in pU, OU and SU 200 GeV per nucleon react ions. When energy density or projectile mass are increased, φ production is enhanced as compared with the yield of muon pairs in the mass continuum (1.7 M μμ c 2 ), whereas the production of ω and ϱ, experimentally unresolved, remains approximately constant. This φ enhancement is in agreement with predictions based on quark-gluon plasma formation and, together with the previously reported J/Ψ suppression, puts severe constraints on a purely hadronic description of nucleus-nucleus collisions.

Published
1991

32. Initial state interactions and J/ψ production in nucleus-nucleus collisions

Author

F. Vazeille, Ph. Gorodetzky, A. Bussiere, C. Baglin, J.-R. Pizzi, Philippe Busson, S. Silva, M. Bedjidian, M.C. Abreu, O. Drapier, J. Fargeix, A. Romana, Joao Varela, L. Fredj, S. Papillon, A. Baldisseri, R. Haroutunian, Didier Contardo, R. Ferreira, J. Castor, Luis Peralta, G. Landaud, J.P. Guillaud, X. Tarrago, B. Chaurand, R. Kossakowski, C. Gerschel, C. Racca, A. Guichard, Carlos Lourenco, L. Kluberg, T. Chambon, J.M. Gago, P. Bordalo, F. Staley, Claude Charlot, A. Devaux, B. Grosdidier, S. Ramos, A. Baldit, P. Force, P. Sonderegger, J.-Y. Grossiord, C. Barriere, P. Liaud, D. Jouan, E. Descroix, Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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 d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-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 Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-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), ALICE, Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), 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)-Université Claude Bernard Lyon 1 (UCBL), NA38, Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), 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), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, Quantitative Biology::Neurons and Cognition, Meson, 010308 nuclear & particles physics, Hadron, Elementary particle, Quarkonium, 01 natural sciences, Nuclear physics, medicine.anatomical_structure, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], 0103 physical sciences, medicine, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon, Nucleus, Boson
Abstract

The mean squared transverse momentum of J/ψ's measured in pCu, pU, OCu, OU and SU collisions at 200 GeV/ nucleon is analyzed in terms of initial state interactions. Taking this effect into account, the mechanism which suppresses the J/ψ production in ion-induced collisions would only have a weak PT dependence.

Published
1991

33. Low-mass dileptons in pA and AA collisions

Author

P.A. Seidl, S. Beedoe, J. Bystricky, J. Carroll, P. Force, J. Gordon, T. Hallman, G. Igo, P. Kirk, G.F. Krebs, E. Lallier, G. Landaud, A. Letessier-Selvon, L. Madansky, H.S. Matis, D. Miller, J. Miller, C. Naudet, G. Roche, L.S. Schroeder, Z.F. Wang, R.C. Welsh, and A. Yegneswaran

Subjects
Excitation function, Physics, Nuclear and High Energy Physics, Particle physics, Spectrometer, High Energy Physics::Phenomenology, Nuclear Theory, Plasma, Kinetic energy, Nuclear physics, Excited state, Transverse momentum, High Energy Physics::Experiment, Nuclear Experiment, Low Mass, Excitation
Abstract

The low-mass ( M + e − continuum has not yet been understood even though the large yield has been documented in a number of high-energy hadron-nucleon and hadron-nucleus experiments. In heavy-ion collisions, effects resulting from the presence of the excited nuclear medium are expected. An understanding of dilepton production at excitation energies in the few-GeV range will aid in the interpretation of dilepton production at ultra-relativistic energies, where it may be a probe of the quark-gluon plasma. The objective of the Dilepton Spectrometer (DLS) collaboration at the BEVALAC is to study the production of e + e − pairs in nucleon-nucleon, proton-nucleus and nucleus-nucleus collisions at bombarding kinetic energies between 1 and 5 A · GeV. The transverse momentum distributions, the mass dependence, and the excitation function of dilepton production give information about the production mechanisms.

Published
1991

34. J/ψProduction in Indium-Indium Collisions at158 GeV/Nucleon

Author

Hiroaki Ohnishi, Laurent Ducroux, B. Chaurand, P. Rosinsky, T. Poghosyan, A. Devaux, Raphael Noel Tieulent, K. Banicz, A. Neves, N. Guettet, H. J. Specht, S. Serci, H. En'yo, A. Colla, J. Seixas, Franck Manso, P. Sonderegger, Alessandro Ferretti, E. Radermacher, Alberto Masoni, Enrico Scomparin, P. Martins, Pietro Cortese, P. Ramalhete, L. Kluberg, Carlos Lourenco, J. Fargeix, P. Parracho, J. Lozano, J. M. Heuser, H. Gulkanian, A. Guichard, A. De Falco, P. Pillot, J. Castor, S. Damjanovic, A. Förster, Corrado Cicalo, G. L. Usai, G. Puddu, Rob Veenhof, Hermine Katharina Wöhri, Michele Floris, Chiara Oppedisano, A. David, Ruben Shahoyan, M. Keil, Roberta Arnaldi, and P. Force

Subjects
Physics, Particle physics, Large Hadron Collider, Muon, 010308 nuclear & particles physics, Nuclear Theory, General Physics and Astronomy, chemistry.chemical_element, Nuclear matter, 01 natural sciences, Super Proton Synchrotron, Nuclear physics, Pair production, chemistry, 0103 physical sciences, Quark–gluon plasma, Nuclear Experiment, 010306 general physics, Nucleon, Indium
Abstract

The NA60 experiment studies muon pair production at the CERN Super Proton Synchrotron. In this Letter we report on a precision measurement of J/{psi} in In-In collisions. We have studied the J/{psi} centrality distribution, and we have compared it with the one expected if absorption in cold nuclear matter were the only active suppression mechanism. For collisions involving more than {approx}80 participant nucleons, we find that an extra suppression is present. This result is in qualitative agreement with previous Pb-Pb measurements by the NA50 experiment, but no theoretical explanation is presently able to coherently describe both results.

Published
2007

35. Low mass dimuon production in proton-nucleus and Indium-Indium collisions

Author

A. Devaux, A. Förster, P. Sonderegger, N. Guettet, Pietro Cortese, Rob Veenhof, P. Force, Markus Keil, Laurent Ducroux, H. J. Specht, S. Serci, A. De Falco, Ralf Peter Averbeck, A. Guichard, P. Pillot, A. Colla, Carlos Lourenco, B. Chaurand, L. Kluberg, H. K. Woehri, S. Damjanovic, C. Oppedisano, P. Ramalhete, Franck Manso, A. David, K. Banicz, J. Castor, E. Radermacher, H. En'yo, J. M. Heuser, Enrico Scomparin, J. Lozano, P. Parracho, Hiroaki Ohnishi, Michele Floris, G. Puddu, P. Rosinsky, P. Martins, Raphael Noel Tieulent, Alberto Masoni, R. Shahoian, C. Cicalo, H. Gulkanian, Roberta Arnaldi, Alessandro Ferretti, A. Drees, G. L. Usai, J. Seixas, and A. Neves

Subjects
Physics, Particle physics, Muon, Large Hadron Collider, Meson, Proton, Mass distribution, Physics::Instrumentation and Detectors, Nuclear Theory, chemistry.chemical_element, Spectral line, Nuclear physics, chemistry, High Energy Physics::Experiment, Nuclear Experiment, Low Mass, Indium
Abstract

The NA60 experiment studied low-mass dimuon production in proton-nucleus and indium-indium collisions at the CERN SPS. While the p-A data can be well described by a superposition of light neutral meson decays, an excess is observed in the heavy-ion data, increasing with collision centrality, with respect to these expected sources. Thanks to the high statistics and good quality of our measurement, we can subtract the muon pairs due to h, h0, w and f decays from the signal dimuon mass distribution. The resulting spectra are compatible with a r spectral function broadening from peripheral to central collisions, with no change in the pole mass.

Published
2007

36. $J/\psi$ and $\psi'$ production and their normal nuclear absorption in proton-nucleus collisions at 400 GeV

Author

Mauro Gallio, Paolo Giubellino, V. Boldea, N. Willis, Marco Monteno, Y. Le Bornec, A. Devaux, G. Borges, S. Serci, Alberto Masoni, Calin Alexa, X. Tarrago, Ara Grigoryan, Massimo Masera, C. Quintans, M. Atayan, H.R. Gulkanyan, J. Fargeix, Sanda Dita, D. Jouan, Stefania Beole, Roberta Arnaldi, M.B. Golubeva, M. P. Comets, J. Castor, P. Bordalo, Corrado Cicalo, A. De Falco, P. Force, Serban Constantinescu, J.-Y. Grossiord, Pietro Cortese, G. Puddu, P. Saturnini, Enrico Scomparin, Mario Sitta, E. Chiavassa, Brigitte Cheynis, P. Petiau, G. L. Usai, Ruben Shahoyan, A. Guichard, A. Piccotti, B. Chaurand, P. Sonderegger, Ermanno Vercellin, Marek Idzik, F. Prino, C. Gerschel, Carlos Lourenco, Alexey Kurepin, L. Kluberg, L. Villatte, N. De Marco, M. Mac Cormick, N.S. Topilskaya, A. Musso, J.-R. Pizzi, Bruno Alessandro, Tatiana Karavicheva, F.F. Guber, Luciano Ramello, L. Riccati, A. Marzari-Chiesa, S. Ramos, G. Dellacasa, Helena Santos, 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), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), 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), 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), NA50, 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), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 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)-Université Claude Bernard Lyon 1 (UCBL), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear reaction, Particle physics, Physics and Astronomy (miscellaneous), Proton, Meson, Hadron, Nuclear Theory, FOS: Physical sciences, Elementary particle, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 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 Physics - Experiment, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Engineering (miscellaneous), Physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Drell–Yan process, Nuclear matter, Quarkonium, High Energy Physics::Experiment
Abstract

We report a new measurement of J/psi, psi' and Drell-Yan cross-sections, in the kinematical domain $-0.425, Comment: Accepted for publication in Euro. Phys. J. C

Published
2007

37. $\psi'$ production in Pb-Pb collisions at 158 GeV/nucleon

Author

Marek Idzik, A. Musso, A. Piccotti, F. Prino, Mauro Gallio, V. Boldea, H.R. Gulkanyan, Paolo Giubellino, P. Bordalo, A. De Falco, J. Fargeix, P. Petiau, A. Marzari-Chiesa, M. Mac Cormick, Alberto Masoni, Alexey Kurepin, P. Saturnini, S. Serci, C. Quintans, M. Atayan, Brigitte Cheynis, M. P. Comets, Massimo Masera, S. Ramos, N. Willis, A. Devaux, Enrico Scomparin, M. Gonin, Sanda Dita, Pietro Cortese, Stefania Beole, E. Chiavassa, Ruben Shahoyan, D. Jouan, A. Guichard, Ara Grigoryan, Ermanno Vercellin, P. Force, A. Romana, Calin Alexa, F.F. Guber, G. Puddu, N. De Marco, Luciano Ramello, G. Dellacasa, G. L. Usai, Helena Santos, B. Chaurand, Mario Sitta, C. Gerschel, Carlos Lourenco, L. Riccati, L. Kluberg, O. Drapier, N.S. Topilskaya, J.-R. Pizzi, X. Tarrago, M.B. Golubeva, Bruno Alessandro, Tatiana Karavicheva, G. Borges, Corrado Cicalo, P. Sonderegger, Marco Monteno, Y. Le Bornec, J. Castor, L. Villatte, Serban Constantinescu, J.-Y. Grossiord, Roberta Arnaldi, 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), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), ALICE, Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), 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)-Université Claude Bernard Lyon 1 (UCBL), NA50, 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), 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)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), 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), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Systematic error, Particle physics, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, Nuclear Theory, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, Momentum, Electromagnetic calorimeter, 0103 physical sciences, High Energy Physics::Experiment, Open charm, Nuclear Experiment (nucl-ex), 010306 general physics, Nucleon, Nuclear Experiment, Engineering (miscellaneous)
Abstract

psi' production is studied in Pb-Pb collisions at 158 GeV/c per nucleon incident momentum. Absolute cross-sections are measured and production rates are investigated as a function of the centrality of the collision. The results are compared with those obtained for lighter colliding systems and also for the J/psi meson produced under identical conditions., Comment: Accepted for publication in Euro. Phys. J. C

Published
2007

38. NA60 results on $p_T$ spectra and the $\rho$ spectral function in In-In collisions

Author

J Seixas, the NA60 Collaboration, R Arnaldi, R Averbeck, K Banicz, J Castor, B Chaurand, C Cicalò, A Colla, P Cortese, S Damjanovic, A David, A De Falco, A Devaux, A Drees, L Ducroux, H En'yo, A Ferretti, M Floris, A Förster, P Force, N Guettet, A Guichard, H Gulkanian, M Keil, L Kluberg, C Lourenço, J Lozano, F Manso, A Masoni, P Martins, A Neves, H Ohnishi, C Oppedisano, P Parracho, P Pillot, G Puddu, E Radermacher, P Ramalhete, P Rosinsky, E Scomparin, S Serci, R Shahoyan, P Sonderegger, H J Specht, R Tieulent, G Usai, R Veenhof, H K Wöhri, 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, Muon, Large Hadron Collider, Meson, 010308 nuclear & particles physics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Spectral line, Nuclear physics, Yield (chemistry), 0103 physical sciences, Mass spectrum, Radial flow, High Energy Physics::Experiment, Spectral function, 010306 general physics, Nuclear Experiment
Abstract

The NA60 experiment at the CERN SPS has studied low-mass muon pairs in 158 AGeV In-In collisions. A strong excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size of close to 400K events and the good mass resolution of about 2% have made it possible to isolate the excess by subtraction of the decay sources (keeping the $\rho$). The shape of the resulting mass spectrum exhibits considerable broadening, but essentially no shift in mass. The acceptance-corrected transverse-momentum spectra have a shape atypical for radial flow and show a significant mass dependence, pointing to different sources in different mass regions., Comment: 4 pages, 4 figures, Quark Matter 2006 conference proceedings

Published
2006

39. $\phi$ meson production in NA60

Author

P. Sonderegger, P. Martins, J. Lozano, Raphael Noel Tieulent, C. Cicalo, Hermine Katharina Wöhri, B. Chaurand, A. De Falco, Alessandro Ferretti, Hiroaki Ohnishi, P. Pillot, N. Guettet, S. Serci, S. Damjanovic, E. Radermacher, H. Gulkanian, Pietro Cortese, H. En'yo, A. Colla, Joao Seixas, M. Keil, H. J. Specht, K. Banicz, F. Manso, Carlos Lourenco, P. Ramalhete, Roberta Arnaldi, Laurent Ducroux, P. Parracho, Alberto Masoni, A. Drees, P. Force, G. L. Usai, A. Devaux, Rob Veenhof, A. Neves, R. Averbeck, L. Kluberg, P. Rosinsky, J. Castor, A. David, Ruben Shahoyan, Michele Floris, Chiara Oppedisano, A. Guichard, J. M. Heuser, Enrico Scomparin, A. Foerster, G. Puddu, 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), Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari (INFN, Sezione di Cagliari), Istituto Nazionale di Fisica Nucleare (INFN), NA60, National Institute for Nuclear Physics (INFN), 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, Particle physics, 25.75.Nq, 25.75.-q, 25.75.Dw, 14.40.Cs, 12.38.Mh, Large Hadron Collider, Muon, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, Nuclear Theory, Elementary particle, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Quality (physics), 0103 physical sciences, Range (statistics), 010306 general physics, Nucleon, Nuclear Experiment, Engineering (miscellaneous), NA49 experiment
Abstract

NA60, presented by M. Floris; NA60 is a fixed-target experiment at the CERN SPS which measured dimuon production in nucleus–nucleus and proton–nucleus collisions. The experiment collected muon pair samples of unprecedented quality in heavy-ion experiments. This paper presents a high quality measurement of the pT distribution of the φ meson, covering a broad pT window. The data were collected in 2003 in In-In collisions at 158 GeV per nucleon. The results, presented as a function of centrality, were studied against several possible sources of systematic effects and proved to be fairly stable. We show that the inverse mT slope measured in In-In collisions, in the φ→μμ decay channel, depends significantly on the range used to perform the fit. When the fit is performed at low transverse momentum, the effective inverse slope increases from peripheral to central collisions, as measured by other experiments. We finally show that our measurement for In-In is compatible with the overall systematics of T slope versus mass, measured in different collision systems by the NA49 experiment.

Published
2006

40. Latest results from NA60

Author

A Förster, the NA60 Collaboration, R Arnaldi, R Averbeck, K Banicz, J Castor, B Chaurand, C Cicalò, A Colla, P Cortese, S Damjanovic, A David, A De Falco, A Devaux, A Drees, L Ducroux, H En'yo, J Fargeix, A Ferretti, M Floris, P Force, N Guettet, A Guichard, H Gulkanian, J M Heuser, M Keil, L Kluberg, C Lourenço, J Lozano, F Manso, A Masoni, P Martins, A Neves, H Ohnishi, C Oppedisano, P Parracho, Ph Pillot, G Puddu, E Radermacher, P Ramalhete, P Rosinsky, E Scomparin, J Seixas, S Serci, R Shahoyan, P Sonderegger, H J Specht, R Tieulent, G Usai, R Veenhof, H K Wöhri, 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, Muon, 010308 nuclear & particles physics, Plane (geometry), Elliptic flow, FOS: Physical sciences, 01 natural sciences, Charged particle, Azimuth, Nuclear physics, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Physics - Experiment, Nuclear Experiment (nucl-ex), Invariant (mathematics), Nuclear Experiment, 010306 general physics, Nucleon, Saturation (chemistry)
Abstract

The NA60 experiment has measured the production of muon pairs and of charged particles in In+In collisions at a beam energy of 158 AGeV. For invariant dimuon masses below the phi the space-time averaged rho spectral function was isolated by a novel procedure. It shows a strong broadening but essentially no shift in mass. The production of J/psi was measured as a function of the collision centrality. As in previous experiments studying Pb+Pb collisions an anomalous supression is observed, setting in at approximately 90 participant nucleons. Using the charged particles the reaction plane was reconstructed. The elliptic flow of charged particles increases with pt showing a saturation for pt > 2GeV/c. For the first time azimuthal distributions for J/psi are shown., 9 pages, 11 figures, talk given at the conference "Strangeness in Quark Matter 2006 (SQM2006)", March 2006, Los Angeles, USA, accepted for publication in Journal of Physics G

Published
2006

41. Bottomonium and Drell-Yan production in p-A collisions at 450 GeV

Author

B. Alessandro, C. Alexa, R. Arnaldi, M. Atayan, S. Beolè, V. Boldea, P. Bordalo, G. Borges, J. Castor, B. Chaurand, B. Cheynis, E. Chiavassa, C. Cicalò, M.P. Comets, S. Constantinescu, P. Cortese, A. De Falco, N. De Marco, G. Dellacasa, A. Devaux, S. Dita, J. Fargeix, P. Force, M. Gallio, C. Gerschel, P. Giubellino, M.B. Golubeva, A. Grigoryan, J.Y. Grossiord, F.F. Guber, A. Guichard, H. Gulkanyan, M. Idzik, D. Jouan, T.L. Karavicheva, L. Kluberg, A.B. Kurepin, Y. Le Bornec, C. Lourenço, M. Mac Cormick, A. Marzari-Chiesa, M. Masera, A. Masoni, M. Monteno, A. Musso, P. Petiau, A. Piccotti, J.R. Pizzi, F. Prino, G. Puddu, C. Quintans, L. Ramello, S. Ramos, L. Riccati, H. Santos, P. Saturnini, E. Scomparin, S. Serci, R. Shahoyan, M. Sitta, P. Sonderegger, X. Tarrago, N.S. Topilskaya, G.L. Usai, E. Vercellin, N. Willis, 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), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), 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), NA50, 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), 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), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 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)-Université Claude Bernard Lyon 1 (UCBL)

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Nuclear Theory, FOS: Physical sciences, Drell–Yan process, chemistry.chemical_element, Tungsten, 01 natural sciences, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), chemistry, 0103 physical sciences, Transverse momentum, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Incident energy, High Energy Physics::Experiment, Beryllium, 010306 general physics, Nuclear Experiment, Particle Physics - Experiment
Abstract

The NA50 Collaboration has measured heavy-quarkonium production in p-A collisions at 450 GeV incident energy (sqrt(s) = 29.1 GeV). We report here results on the production of the Upsilon states and of high-mass Drell-Yan muon pairs (m > 6 GeV). The cross-section at midrapidity and the A-dependence of the measured yields are determined and compared with the results of other fixed-target experiments and with the available theoretical estimates. Finally, we also address some issues concerning the transverse momentum distributions of the measured dimuons., 18 pages, 9 figures, to be published in Phys. Lett. B

Published
2006

42. φ Production in Proton-Nucleus and Indium-Indium Collisions at the CERN SPS

Author

P. Pillot, S. Serci, Hiroaki Ohnishi, A. Colla, P. Rosinsky, G. Puddu, Raphael Noel Tieulent, Alessandro Ferretti, J. Lozano, A. Neves, P. Martins, A. Guichard, P. Sonderegger, B. Chaurand, R. Averbeck, Alberto Masoni, Pietro Cortese, P. Ramalhete, Michele Floris, S. Damjanovic, M. Keil, Roberta Arnaldi, H. Gulkanian, Chiara Oppedisano, Carlos Lourenco, Enrico Scomparin, P. Force, Laurent Ducroux, L. Kluberg, P. Parracho, J. Castor, Corrado Cicalo, Ruben Shahoyan, A. De Falco, A. Drees, G. L. Usai, Joao Seixas, A. David, Rob Veenhof, H. J. Specht, E. Radermacher, A. Devaux, K. Banicz, Hermine Katharina Wöhri, J. M. Heuser, N. Guettet, H. En'yo, and Franck Manso

Subjects
Physics, Particle physics, Large Hadron Collider, Meson, Proton, Silicon, Nuclear Theory, Inverse, chemistry.chemical_element, law.invention, Nuclear physics, Telescope, chemistry, law, Nuclear Experiment, Nucleon, Indium
Abstract

The quality of the dimuon measurements made by NA60, in proton‐nucleus and heavy‐ion collisions, is much better than that reached by previous experiments, such as NA38 and NA50. The most important improvement is due to the use of a radiation‐tolerant silicon vertex telescope, placed immediately downstream of the target. This allows NA60 to do a high quality measurement of φ meson yields and pT distributions.This paper presents results obtained in p‐Be, p‐In and p‐Pb collisions at 400 GeV, from data collected in 2002, and in In‐In collisions at 158 AGeV, as a function of centrality, from the 2003 running period. In particular, we show that the inverse mT slope measured in In‐In collisions, in the φ → μμ decay channel, increases with the number of nucleons participating in the collisions, rather than following a flat trend as seen in the NA50 data collected in the same decay channel but restricted to high pT values. We also show that our measurements seem to agree with the values previously measured by NA49...

Published
2006

43. Results from NA60 experiment at the CERN SPS

Author

Pietro Cortese, Carlos Lourenco, E. Radermacher, P. Rosinsky, Hermine Katharina Wöhri, P. Ramalhete, Enrico Scomparin, P. Sonderegger, M. Keil, R. Averbeck, P. Parracho, J. Lozano, Roberta Arnaldi, S. Damjanovic, A. Guichard, H. J. Specht, J. M. Heuser, L. Kluberg, P. Pillot, A. Devaux, A. David, P. Force, A. De Falco, N. Guettet, B. Chaurand, A. Colla, K. Banicz, Raphael Noel Tieulent, Alessandro Ferretti, H. En'yo, S. Serci, A. Drees, Franck Manso, Alberto Masoni, Hiroaki Ohnishi, G. L. Usai, A. Neves, G. Puddu, Laurent Ducroux, H. Gulkanian, Joao Seixas, P. Martins, Rob Veenhof, J. Castor, Corrado Cicalo, Ruben Shahoyan, Michele Floris, Chiara Oppedisano, 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), 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), 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), NA60, 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), and Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Particle physics, Large Hadron Collider, Muon, Physics::Instrumentation and Detectors, Nuclear Theory, 020206 networking & telecommunications, 02 engineering and technology, heavy ion collisions $\rho$ meson, open charm, 25.75.-q,25.75.Dw,14.40.Cs, Nuclear physics, Pair production, J/$\psi$ suppression, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], 0202 electrical engineering, electronic engineering, information engineering, High Energy Physics::Experiment, 020201 artificial intelligence & image processing, Invariant mass, Open charm, Nuclear Experiment, Nucleon, Low Mass
Abstract

NA60; International audience; The NA60 experiment studies open charm and prompt dimuon production in proton-nucleus and nucleus-nucleus collisions at the CERN SPS. During 2003 the experiment collected data in indium-indium collisions at 158 GeV per nucleon. In this paper the first results on low mass dimuons, open charm production and J/$\psi$ suppression are presented.

Published
2006

44. First Measurement of the $\rho$ Spectral Function in High-Energy Nuclear Collisions

Author

M. Keil, Roberta Arnaldi, P. Force, A. Neves, A. Devaux, P. Pillot, H. J. Specht, S. Serci, P. Rosinsky, P. Parracho, K. Banicz, Hermine Katharina Wöhri, R. Averbeck, Laurent Ducroux, Raphael Noel Tieulent, B. Chaurand, Michele Floris, A. De Falco, Alberto Masoni, P. Ramalhete, G. Puddu, Chiara Oppedisano, Hiroaki Ohnishi, Joao Seixas, A. Förster, A. Colla, E. Radermacher, Alessandro Ferretti, Ruben Shahoyan, J. Fargeix, Andréia Márcia Santos de Souza David, H. Gulkanian, N. Guettet, Franck Manso, P. Martins, Enrico Scomparin, H. En'yo, J. Lozano, A. Drees, A. Guichard, G. L. Usai, L. Kluberg, J. M. Heuser, P. Sonderegger, S. Damjanovic, Pietro Cortese, Carlos Lourenco, J. Castor, Corrado Cicalo, Rob Veenhof, 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
Particle physics, pion-pion interactions, Meson, 25.75.-q, 12.38.Mh, 13.85.Qk, Hadron, FOS: Physical sciences, General Physics and Astronomy, 7. Clean energy, 01 natural sciences, Nuclear physics, 0103 physical sciences, quantum chromodynamics, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Physics - Experiment, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, Quantum chromodynamics, Annihilation, Muon, 010308 nuclear & particles physics, rho mesons, meson leptonic decay, Pair production, Quark–gluon plasma, Mass spectrum, heavy ion-nucleus reactions, High Energy Physics::Experiment
Abstract

We report on a precision measurement of low-mass muon pairs in 158 AGeV indium-indium collisions at the CERN SPS. A significant excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size of 360 000 dimuons and the good mass resolution of about 2% allow us to isolate the excess by subtraction of the decay sources. The shape of the resulting mass spectrum is consistent with a dominant contribution from pi+pi-->rho-->mu+mu- annihilation. The associated space-time averaged rho spectral function shows a strong broadening, but essentially no shift in mass. This may rule out theoretical models linking hadron masses We report on a precision measurement of low-mass muon pairs in 158 AGeV indium-indium collisions at the CERN SPS. A significant excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size of 360 000 dimuons and the good mass resolution of about 2% allow us to isolate the excess by subtraction of the decay sources. The shape of the resulting mass spectrum is consistent with a dominant contribution from pi+pi-->rho-->mu+mu- annihilation. The associated space-time averaged rho spectral function shows a strong broadening, but essentially no shift in mass. This may rule out theoretical models linking hadron masses

Published
2006

45. ALICE: Physics Performance Report, Volume II

Author

Alessandro, B. Antinori, F. Belikov, J. A. Blume, C. and Dainese, A. Foka, P. Giubellino, P. Hippolyte, B. Kuhn, C. Martinez, G. Monteno, M. Morsch, A. Nayak, T. K. and Nystrand, J. Noriega, M. Lopez Paic, G. Pluta, J. and Ramello, L. Revol, J-P Safarik, K. Schukraft, J. Schutz, Y. Scomparin, E. Snellings, R. Baillie, O. Villalobos and Vercellin, E. Cortese, P. Dellacasa, G. Ramello, L. and Sitta, M. Ahmad, N. Ahmad, S. Ahmad, T. Bari, W. and Irfan, M. Zafar, M. Botje, M. Kuijer, P. G. Snellings, R. Belogianni, A. Christakoglou, P. Ganoti, P. Petridis, A. Roukoutakis, F. Spyropoulou-Stassinaki, M. Vassiliou, M. and Bruno, G. E. Cali, I. A. Caselle, M. De Cataldo, G. and Di Bari, D. Elia, D. Fini, R. A. Ghidini, B. Lenti, V. and Manzari, V. Mastroserio, A. Minafra, F. Nappi, E. and Navach, F. Pastore, C. Paticchio, V. Perrino, D. Posa, F. Santoro, R. Sgura, I Volpe, G. Corsi, F. De Venuto, D. Fratino, U. Marzocca, C. Tauro, A. Li, X. and Liu, Z. Lu, S. Lu, Z. Meng, Q. Sa, B. Yuan, J. and Zhou, J. Zhou, S. Alme, J. Bablok, S. Klovning, A. and Nystrand, J. Pommereesche, B. Richter, M. Rohrich, D. and Ullaland, K. Yang, H. Helstrup, H. Hetland, K. F. and Kileng, B. Roed, K. Choudhury, R. K. Dash, S. Mahapatra, D. P. Mishra, D. Phatak, S. C. Sahoo, R. Daniel, L. and Evans, D. Jones, G. T. Jovanovic, P. Jusko, A. Kinson, J. B. Platt, R. Lietava, R. Takaki, J. D. Tapia Baillie, O. Villalobos Alici, A. Antinori, S. Antoniolo, P. and Arcelli, S. Bari, G. Basile, M. Romeo, G. Cara and Cifarelli, L. Cindolo, F. Falchieri, D. Gabrielli, A. and Gandolfi, E. Hatzifotiadou, D. Laurenti, G. Luvisetto, M. I. and Nania, R. Noferini, F. Palmonari, F. Pesci, A. and Sartorelli, G. Sciolo, G. Vacca, G. P. Valenti, G. and Venturi, G. Williams, M. C. S. Zampolli, C. Zichichi, A. and Cerny, V. Janik, R. Lucan, L. Pikna, M. Pisut, J. and Pisutova, N. Sitar, B. Strmen, P. Szarka Zagiba, M. and Aiftimieri, C. Catanescu, V. Legrand, C. I. Petrovici, M. and Pop, A. Schiaua, C. Simion, V. Barnafoldi, G. and Boldizsar, L. Denes, E. Fodor, Z. Futo, E. Kiss, T. and Levai, P. Palla, G. Zimanyi, J. Atanassov, I. Basciu, S. and Cicalo, C. De Falco, A. Floris, M. Masoni, A. Mura, D. Puddu, G. Serci, S. Siddi, S. Usai, G. Badala, A. and Barbera, R. Lo Re, G. Palmeri, A. Pappalardo, G. S. and Pulvirenti, A. Riggi, F. Anelli, G. Augustin, I. and Augustinus, A. Baechler, J. Belikov, J. A. Betev, L. and Boccardi, A. Brun, R. Burns, M. Buncic, P. Campagnolo, R. Campbell, M. Carena, F. Carena, W. Carminati, F. and Chapeland, S. Cheshkov, C. Chochula, P. Christiansen, P. and Colla, A. Belbute, B. F. Correia Davenport, M. de Groot, J. and Di Mauro, A. Divia, R. Engster, C. Evrard, S. and Fabjan, C. W. Feng, L. Flierl, D. Formenti, F. Fuchs, U. and Garcia Lopez, A. Gheata, A. Gheata, M. and Gonzalez-Gutierrez, C. Grosso, R. Gruwe, M. Gustafsson, H. A. Hoedelmoser, H. Hristov, P. Ivanov, M. Jirden, L. and Jorgensen, C. Junique, A. Kapusta, S. Kickinger, W. and Klempt, W. Kluge, A. Leistam, L. Lo, J. P. Noriega, M. Lopez Lourenco, C. Makhylyueve, I. Marin, J. C. and Martinengo, P. Meunier-Picard, D. Meoni, M. Morel, M. and Morsch, A. Mota, B. Muller, H. Musa, L. Nayak, T. K. and Nilsson, P. Nouais, D. Osmic, F. Perini, D. Pestotnik, R. Peters, A. Morais, V. Pinto Popescu, S. Rademakers, F. Revol, J. P. Riedler, P. Riegler, W. Safarik, K. and Schossmaier, K. Schukraft, J. Schutz, Y. Silva Loureiro, P. A. Soos, C. Stefanini, G. Swoboda, D. Tadel, M. and Taureg, H. Tavlet, M. Tissot-Daguette, P. de Matos, C. Torcato Vande Vyvre, P. Vanuxem, J. P. Aggarwal, M. M. and Bhati, A. K. Kumar, A. Sharma, M. Sood, G. Baldit, A. and Barret, V. Bastid, N. Blanchard, G. Castor, J. and Crochet, P. Daudon, F. Devaux, A. Dupieux, P. Force, P. and Grigoryan, S. Guerin, F. Guerin, F. Guernane, R. and Insa, C. Jouve, F. Lecoq, J. Manso, F. Rosnet, P. and Royer, L. Saturnini, P. Savinel, G. Humanic, T. J. and Kotov, I. V. Lisa, M. Nilsen, B. S. Truesdale, D. and Johnson, D. Bearden, I. Boggild, H. Christensen, C. H. and Gaardhoje, J. J. Gulbrandtsen, K. Nielsen, B. S. Renault, G. and Bartke, J. Gladysz-Dziadus, E. Kornas, E. Kowalski, M. and Rybicki, A. Wroblewski, A. Andronic, A. Antonczyk, D. and Badura, E. Bailhache, R. Berdermann, E. Braun-Munzinger, P. Busch, O. Ciobanu, M. Foka, P. Frankenfeld, U. and Garabatos, C. Gutbrod, H. Lippmann, C. Malzacher, P. and Marin, A. Miskowiec, D. Radomski, S. Schmidt, H. R. and Schwarz, K. Sedykh, K. Simon, R. S. Soyk, D. Stelzer, H. and Stockmeier, M. Tziledakis, G. Vranic, D. Wiechula, J. and Bonnes, U. Kraus, I. Oeschler, H. Appelshauser, H. and Blume, C. Dietel, T. Gazdzicki, M. Hartig, M. Kliemant, M. Kniege, S. Kolleger, T. Kramer, F. Lange, F. and Loizides, C. Ploskon, M. Renfordt, R. Sommer, W. Stock, R. Strobele, H. Berdnikov, Ya Ivanov, V Khanzadeev, A. and Miftakhov, N. Nicoulin, V. Polyakov, V. Rostchin, E. and Samsonov, V. Tarasenkova, O. Tarakanov, V. Zhalov, M. and Lopez Torres, E. Abrahantes Quintana, A. Diaz Valdes, R. and Angelov, T. Alt V. Cuveland, J. Gutfleish, M. Kalcher, S. and Lindenstruth, V. Panse, R. Reichling, C. Schneider, R. and Steinbeck, T. Troger, H. Tilsner G. Wiebalck, A. Adler, C. Emschermann, D. Glassel, P. Herrmann, N. Ludolphs, W. and Mahmoud, T. Mercado, J. Milosevic, J. Oyama, K. and Rusanov, I. Schnicker, R. Shukla, P. Soltveit, H. C. and Stachel, J. Vulpescu, B. Windelband, B. Yurevich, S. and Shigaki, K. Sugitate, T. Raniwala, S. Badyal, S. K. and Bala, R. Bhasin, A. Gupta, A. Gupta, V. K. Mahajan, S. and Mangotra, L. K. Potukuchi, B. V. K. S. Sambyal, S. S. and Akichine, P. G. Arefiev, V. A. Baatar, T. Batiounia, B. V. and Chepurnov, V. F. Chernenko, S. A. Dodokhov, V. K. and Fateev, O. V. Fedunov, A. G. Haiduc, M. Hasegun, D. and Kadychevsky, V. G. Kharadze, G. Khurelbaatar, B. and Koshurnikov, E. K. Lioubochits, V. C. Lobanov, V. I. and Malinina, L. V. Minaev, Y. I. Nioradze, M. Nomokonov, P. V. and Panebrattsev, Y. A. Penev, V. N. Pismennaya, V. G. and Pocheptsov, T. A. Roufanov, I. Shabratova, G. S. Shestakov, V. Shkloskaya, A. I. Sorin, A. S. Suleimanov, M. K. and Tevzadze, Y. Togoo, R. Vodopianov, A. S. Yurevich, V. I. and Zanevsky, Y. V. Zaporojets, S. A. Zinchenko, A. I. Aysto, J. and Bondila, M. Lyapin, V. Oinonen, M. Malkiewicz, T. and Ruuskanen, V. Seppanen, H. Trzaska, W. Yamaletkinov, S. and Jung, H. T. Jung, W. Kim, D. W. Kim, H. N. Kim, J. S. and Lee, K. S. Lee, S. C. Blank, T. Gemmeke, H. Bochek, G. L. Dovbnya, A. N. Kulibaba, V. I. Maslov, N. I. and Naumov, S. V. Ovchinnik, V. D. Potin, S. M. Starodubtsev, A. F. Borshchov, V. N. Chykalov, O. Kaurova, L. Kiprich, S. K. Klymova, L. Listratenko, O. M. Mykhylova, M. and Protenko, M. Reznik, O. Starkov, V. E. Kadenko, I. and Martynov, Y. Molodtsov, S. Sinyukov, Y. Zinovjev, G. and Bhattacharya, P. Bose, S. Chatterjee, S. Chattopadhyay, S. and Das, D. Das, I. Dutt-Mazumder, A. K. Majumdar, N. and Mukhopadhyay, S. Pal, S. Paul, L. Roy, P. Sanyal, A. and Sarkar, S. Sen, P. Sen, S. K. Sinha, B. C. Sinha, T. and Ahammed, Z. Bhaskar, P. Chattopadhyay, S. Das, D. Das, S. Majumdar, M. R. Dutta Ganti, M. S. Ghosh, P. Mohanty, B. Netrakanti, P. K. Pal, S. Singaraju, R. N. Singhal, V. Sinha, B. Viyogi, Y. P. Hartung, G. Krawutschke, T. and Ban, J. Bombara, M. Dirner, A. Hnatic, M. Kralik, I. and Kravcakova, A. Krivan, F. Krivda, M. Martinska, G. and Pastircak, B. Sandor, L. Urban, J. Vrlakova, J. and Cinausero, M. Fioretto, E. Prete, G. Ricci, R. A. and Vannucci, L. Branco, P. Carvalho, R. Seixas, J. Vilela Mendes, R. Oskarsson, A. Osterman, L. Otterlund, I. and Stenlund, E. A. Cheynis, B. Ducroux, L. Grossiord, J. Y. and Guichard, A. Pillot, P. Rapp, B. Tieulent, R. Molina, J. R. Alfaro Ayala, A. Moreno, E. Belmont Contreras, J. G. and Cuautle, E. D'Olivo, J. C. Dominguez, I. Flores, A. and Grabski, V. Corral, G. Herrera Linares, M. Martinez, M. I. and Martinez Davalos, A. Menchaca-Rocha, A. Montano Zetina, L. M. Nellen, L. Paic, G. del Pino, J. Reyes, P. and Sandoval, A. Vergara, S. Zepeda, A. Feshchenko, V. A. and Golubeva, M. B. Gorlychev, V. G. Guber, F. F. Karavichev, O. V. Karavicheva, T. L. Karpechev, E. V. Kurepin, A. B. and Maevskaya, A. I. Marin, V. V. Pshenichnov, I. A. Razin, V. I. Reshetin, A. I. Shileev, K. A. Topil'skaia, N. S. and Akindinov, A. N. Golovine, V. Kaidalov, A. B. Kats, M. M. and Kiselev, I. T. Kisselev, S. M. Lioublev, E. Martemianov, M. Martemiyanov, A. N. Polozov, P. A. Serov, V. S. and Smirnitski, A. V. Tchoumakov, M. M. Vetlitski, I. A. and Volochine, K. G. Vorobiev, L. S. Zagreev, B. V. Aleksandrov, D. Antonenko, V. Beliaev, S. Fokine, S. Ippolitov, M. and Karadjev, K. Koutcheriaev, I. Lebedev, V. Manko, V. I. and Moukhanova, T. Nianine, A. Nikolaev, S. Nikouline, S. and Patarakine, O. Peressounko, D. Sibiriak, I. Tsvetkov, A. and Vasiliev, A. Vinogradov, A. Yushmanov, I Grigoriev, V. A. Kaplin, V. A. Loginov, V. A. Nandi, B. K. Varma, R. and Chandratre, V. Kataria, V. Baumann, C. Glasow, R. and Gottschlag, H. Grosse-Oetringhaus, J. F. Heine, N. and Klein-Bosing, C. Reygers, K. Santo, R. Verhoeven, W. and Wessels, J. Wilk, A. Aphecetche, L. Berny, R. Bouvier, S. Conesa-Balbastre, G. Conesa-del-Valle, Z. Cussonneau, J. P. Delagrange, H. Dialinas, M. Finck, C. Erazmus, B. and Germain, M. Lefevre, F. Luquin, L. Martinez, G. Renard, C. Roy, C. Tournaire, A. Frolov, A. R. Pestov, I. N. and Awes, T. Cherney, M. Gorbunov, Y. Bimbot, L. Chambert, V. Charpy, A. Comets, M. P. Courtat, P. Drouet, S. and Edelbruck, P. Espagnon, B. Hfrivnacova, I. Kunne, R. Le Bornec, Y. Mac Cormick, M. Peyre, J. Pouthas, J. and Bravina, L. Lovhoiden, G. Skaali, B. Tveter, T. S. Vik, T. Antinori, F. Dainese, A. Dima, R. Fabris, D. and Faivre, J. Lunardon, M. Morando, M. Moretto, S. Pepato, A. Quercigh, E. Scarlassara, F. Segato, G. Turrisi, R. and Viesti, G. Choi, J. Beitlerova, A. Mares, J. Polak, K. Zavada, P. Petracek, V. Pachr, M. Skoda, L. and Bogolyubsky, M. Yu Khaoustov, G. V. Kharlov, Yu V. Minaev, N. G. Petrov, V. S. Polichtchouk, B. V. Sadovsky, S. A. and Senko, V. A. Soloviev, A. S. Stolpovsky, P. V. Victorov, V. A. Fernandez Tellez, A. Gamez Flores, E. Lopez-Ramirez, R. and Ortiz-Velczquez, A. Pagliarone, C. Roman-Lopez, S. and Tejeda-Munoz, G. Vargas, A. Villasenor Cendejas, L. Adamova, D. Kouchpil, S. Kouchpil, V. Kugler, A. Sumbera, M. and Wagner, V. Di Liberto, S. Mazzoni, M. A. Meddi, F. and Urciuoli, G. M. Cleymans, J. de Vaux, G. Fearick, R. W. and Szostak, A. Vilakazi, Z. Z. Anfreville, M. Baldisseri, A. and Becker, B. Borel, H. Castillo, J. Charvet, J. L. and Combet, M. Gosset, J. Hardy, P. Herlant, S. Orsini, F. and Penichot, Y. Pereira, H. Staley, F. M. Usseglio, M. and De Caro, A. De Gruttola, D. De Pasquale, S. Di Bartolomeo, A. Girard, M. Fusco Grella, G. Guarnaccia, C. Guida, M. and Romano, G. Sellitto, S. Silvestri, R. Virgili, T. and Basmanov, V. Budnikov, D. Demanov, V. Ianowski, V. and Ilkaev, R. Ivanov, A. Khlebnikov, A. Kouryakin, A. and Mikhailov, E. Nazarenko, S. Pavlov, V. Philchagin, S. and Punin, A. Punin, V. Poutevskoi, S. Rybin, A. Selin, I. and Smetanin, M. Telnov, A. Treskov, S. Vikhlyantsev, O. and Vinogradov, I Vyushin, A. Zavyalov, N. Zhelezov, S. and Zhitnik, A. Gotovac, S. Mudnic, E. Vidak, L. Asryan, A. G. Braun, M. A. Derkach, D. A. Feofilov, G. A. Igolkin, S. N. Ivanov, A. S. Kolevatov, R. S. Kolojvari, A. A. and Kondratiev, V. P. Naumenko, P. A. Toulina, T. A. Valiev, F. F. Vechernin, V. V. Vinogradov, L. I. Baudot, J. Bonnet, D. Coffin, J. P. Estienne, M. Hippolyte, B. Kuhn, C. and Lutz, J. R. Vernet, R. Hamagaki, H. Ozawa, K. Bonvicini, V. Borysov, O. Bosisio, L. Bregant, M. Camerini, P. and Contin, G. Faleschini, F. Fragiacomo, E. Grion, N. and Margagliotti, G. Piano, S. Rachevskaya, I. Rachevski, A. and Rui, R. Vacchi, A. Alessandro, B. Arnaldi, R. Bagnasco, S. Batigne, G. Beole, S. Bruna, E. Cerello, P. and Chiavassa, E. Cobanoglu, O. Coli, S. Crescio, E. De Marco, N. De Remigis, P. Ferretti, A. Gagliardi, M. and Gallio, M. Gaudichet, L. Gemme, R. Giraudo, G. and Giubellino, P. Idzik, M. Martoiu, S. Chiesa, A. Marzari and Masera, M. Mazza, G. Mereu, P. Monteno, M. Musso, A. and Oppedisano, C. Piccotti, A. Poggio, F. Prino, F. and Riccati, L. Rivetti, A. Scomparin, E. Stocco, D. and Tosello, F. Toscano, L. Travaglia, G. Vercellin, E. and Werbrouck, A. Wheadon, R. Yermia, F. Miake, Y. Esumi, S. and Buskop, J. J. F. De Haas, A. P. Ivan, C. Kamermans, R. and Mischke, A. Nooren, G. Oskamp, C. J. Peitzmann, Th. and Simili, E. Sokolov, O. Van Den Brink, A. Van Eijndhoven, N. and Enyo, H. Fujiwara, K. Kano, H. Onishi, H. Deloff, A. and Dobrowolski, T. Karpio, K. Malek, M. Malinowski, H. and Redlich, K. Siemiarczuk, T. Stefanek, G. Tykarski, L. and Wilk, G. Chajecki, Z. Gos, H. Janik, M. Jedynak, M. and Kisiel, A. Pawlak, T. J. Peryt, W. S. Pluta, J. and Skowronski, P. Slodkowski, M. Szuba, P. Traczyk, T. and Conner, E. S. Keidel, R. Cai, X. Ding, H. T. Liu, H. and Wang, X. R. Yang, H. Y. Yin, Z. B. Zhou, D. C. Cao, X. and Li, Q. Liu, Y. Z. Su, G. Tan, L. Zhu, G. X. and Atayan, M. Grigoryan, A. Gulkanyan, H. Harutyunyan, A. and Hayrapetyan, A. Kakoyan, V. Poghosyan, M. Sargsyan, G. and Anticic, T. Kadija, K. Susa, T. Arleo, F. Armesto, N. and Aurenche, P. Benhabib, L. Bogdanov, A. Borghini, N. and Carrer, N. Csorgo, T. Gupta, S. Heinz, U. W. Jacobs, P. M. Lednicky, R. Letessier, J. Mrowczynski, S. Rafelski, J. Ranft, J. Silvermyr, D. Wiedemann, U. A. Scapparone, E. ALICE Collaboration

Subjects
Nuclear Experiment
Abstract

ALICE is a general-purpose heavy-ion experiment designed to study the physics of strongly interacting matter and the quark-gluon plasma in nucleus-nucleus collisions at the LHC. It currently involves more than 900 physicists and senior engineers, from both the nuclear and high-energy physics sectors, from over 90 institutions in about 30 countries. The ALICE detector is designed to cope with the highest particle multiplicities above those anticipated for Pb-Pb collisions (dN(ch)/dy up to 8000) and it will be operational at the start-up of the LHC. In addition to heavy systems, the ALICE Collaboration will study collisions of lower-mass ions, which are a means of varying the energy density, and protons (both pp and pA), which primarily provide reference data for the nucleus-nucleus collisions. In addition, the pp data will allow for a number of genuine pp physics studies. The detailed design of the different detector systems has been laid down in a number of Technical Design Reports issued between mid-1998 and the end of 2004. The experiment is currently under construction and will be ready for data taking with both proton and heavy-ion beams at the start-up of the LHC. Since the comprehensive information on detector and physics performance was last published in the ALICE Technical Proposal in 1996, the detector, as well as simulation, reconstruction and analysis software have undergone significant development. The Physics Performance Report (PPR) provides an updated and comprehensive summary of the performance of the various ALICE subsystems, including updates to the Technical Design Reports, as appropriate. The PPR is divided into two volumes. Volume I, published in 2004 (CERN/LHCC 2003-049, ALICE Collaboration 2004 J. Phys. G: Nucl. Part. Phys. 30 1517-1763), contains in four chapters a short theoretical overview and an extensive reference list concerning the physics topics of interest to ALICE, the experimental conditions at the LHC, a short summary and update of the subsystem designs, and a description of the offline framework and Monte Carlo event generators. The present volume, Volume II, contains the majority of the information relevant to the physics performance in proton-proton, proton-nucleus, and nucleus-nucleus collisions. Following an introductory overview, Chapter 5 describes the combined detector performance and the event reconstruction procedures, based on detailed simulations of the individual subsystems. Chapter 6 describes the analysis and physics reach for a representative sample of physics observables, from global event characteristics to hard processes.

Published
2006

46. Design and Performance of the ALICE Muon Trigger System

Author

S. Grigoryan, A. Baldit, Franck Manso, G. Travaglia, L. Royer, Pietro Cortese, Chiara Oppedisano, F. Guerin, G. Blanchard, P. Mereu, F. Jouve, P. Crochet, A. Devaux, E. Chiavassa, F. Yermia, P. Saturnini, A. Colla, Enrico Scomparin, Alessandro Ferretti, A. Piccotti, G. Dellacasa, F. Poggio, Pascal Dupieux, P. Rosnet, Roberta Arnaldi, Nicole Bastid, Mauro Gallio, P. Force, Martino Gagliardi, A. Musso, B. Forestier, N. De Marco, R. Guernane, R. Gemme, Valerie Ramillien Barret, C. Insa, Ermanno Vercellin, 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 ALICE

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Resistive touchscreen, Large Hadron Collider, Muon, 010308 nuclear & particles physics, Physics::Instrumentation and Detectors, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Measure (mathematics), Atomic and Molecular Physics, and Optics, Nuclear physics, Data acquisition, Muon spectrometer, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], ALICE (propellant), 010306 general physics, Nuclear Experiment, Communication channel
Abstract

ALICE; International audience; The Forward Muon Spectrometer is one of the main components of ALICE, the dedicated heavy-ion experiment at the LHC. Its main goal is to measure heavy quarkonia (J/ψ and families) production in their μ+μ− decay channel. The muon trigger has to match the maximum trigger rate of about 1 kHz which can be handled by the DAQ. Therefore an event selection is performed by applying a suitable pt cut on each muon of the pair. The trigger system is based on Resistive Plate Chambers. The experimental conditions, the trigger architecture, its principle and its performance predicted by simulation are presented.

Published
2005

47. First measurement of the rho spectral function in nuclear collisions

Author

A. Neves, B. Chaurand, H. Gulkanian, L. Kluberg, K. Banicz, Alberto Masoni, N. Guettet, P. Ramalhete, H. En'yo, E. Radermacher, P. Rosinsky, A. De Falco, Pietro Cortese, H. J. Specht, S. Serci, P. Martins, A. Forster, Laurent Ducroux, A. Guichard, Alessandro Ferretti, Carlos Lourenco, Enrico Scomparin, A. Colla, G. Puddu, P. Force, A. Devaux, P. Sonderegger, S. Damjanovic, R. Averbeck, Raphael Noel Tieulent, J. M. Heuser, P. Parracho, F. Manso, J. Fargeix, A. Drees, G. L. Usai, J. Castor, Rob Veenhof, Hiroaki Ohnishi, Ruben Shahoyan, Michele Floris, A. David, Chiara Oppedisano, Hermine Katharina Wöhri, Joao Seixas, J. Lozano, Pillot Ph, C. Cicalo, M. Keil, Roberta Arnaldi, 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), Tamás Csörgő, Gábor Dávid, Péter Lévai and Gábor Papp, 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 and High Energy Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Physics::Instrumentation and Detectors, Hadron, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, 0103 physical sciences, Nuclear Physics - Experiment, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Engineering (miscellaneous), Physics, Muon, Annihilation, Large Hadron Collider, 010308 nuclear & particles physics, Yield (chemistry), Mass spectrum, High Energy Physics::Experiment, Spectral function
Abstract

The NA60 experiment at the CERN SPS has studied low-mass muon pairs in 158 AGeV In-In collisions. A strong excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size close to 400K events and the good mass resolution of about 2% made it possible to isolate the excess by subtraction of the decay sources. The shape of the resulting mass spectrum shows some non-trivial centrality dependence, but is largely consistent with a dominant contribution from pi+pi- ->rho ->mu+mu- annihilation. The associated rho spectral function exhibits considerable broadening, but essentially no shift in mass. The pT-differential mass spectra show the excess to be much stronger at low pT than at high pT. The results are compared to theoretical model predictions; they tend to rule out models linking hadron masses directly to the chiral condensate., 6 pages, 9 figures, To appear in the proceedings of Hot Quarks 2006, Villasimius, Italy, 15-20 May 2006

Published
2005

48. Dimuon and charm production in In-In collisions at the CERN SPS

Author

N. Guettet, K. Banicz, A. Colla, B. Chaurand, Enrico Scomparin, E. Radermacher, H. En'yo, M. Keil, J. Lozano, A. Förster, Alessandro Ferretti, H. J. Specht, Hermine Katharina Wöhri, P. Parracho, J. Castor, Alberto Masoni, A. Guichard, P. Ramalhete, Roberta Arnaldi, P. Rosinsky, A. Devaux, Hiroaki Ohnishi, J. M. Heuser, P. Force, S. Serci, R. Averbeck, A. Neves, P. Martins, Rob Veenhof, L. Kluberg, P. Sonderegger, G. Puddu, Joao Seixas, Pietro Cortese, Ruben Shahoyan, Raphael Noel Tieulent, Pillot Ph, Carlos Lourenco, Laurent Ducroux, A. De Falco, A. David, H. Gulkanian, C. Cicalo, S. Damjanovic, Michele Floris, Chiara Oppedisano, J Fargeix, A. Drees, G. L. Usai, F. Manso, 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), Tamás Csörgő, Gábor Dávid, Péter Lévai and Gábor Papp, 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, Range (particle radiation), Particle physics, Muon, Large Hadron Collider, Meson, Proton, 010308 nuclear & particles physics, Nuclear Theory, 01 natural sciences, 7. Clean energy, Nuclear physics, Pair production, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Invariant mass, High Energy Physics::Experiment, Charm (quantum number), 010306 general physics, Nuclear Experiment
Abstract

The NA60 experiment studies muon pair production with proton and Indium beams. It is a second generation experiment, designed to answer specific questions left open, in the leptonic sector, by the previous round of SPS experiments, finished in 2000. The results presented in this paper cover the dimuon invariant mass range from the threshold to the J/ ψ . The main physics topics that we address include the in-medium modifications of the ρ meson, the origin of the dimuon excess observed between the ϕ and the J/ ψ , and the study of the anomalous J/ ψ suppression. For each of these subjects, the NA60 results represent a significant step forward towards a deeper understanding of the physics of heavy ion collisions at SPS energies.

Published
2005

49. $\phi$ production in p-A and In-In collisions

Author

M. Keil, P. Parracho, Carlos Lourenco, Roberta Arnaldi, J. M. Heuser, Alberto Masoni, P. Rosinsky, Franck Manso, Enrico Scomparin, P. Pillot, H. J. Specht, Laurent Ducroux, G. Puddu, P. Force, P. Martins, A. Drees, A. Neves, Hermine Katharina Wöhri, A. Devaux, G. L. Usai, A. David, Alessandro De Falco, Ruben Shahoyan, B. Chaurand, P. Sonderegger, K. Banicz, R. Averbeck, S. Damjanovic, N. Guettet, J. Lozano, L. Kluberg, S. Serci, J. Castor, H. En'yo, A. Guichard, Corrado Cicalo, Michele Floris, A. De Falco, E. Radermacher, Chiara Oppedisano, A. Colla, H. Gulkanian, Alessandro Ferretti, Raphael Noel Tieulent, Rob Veenhof, P. Ramalhete, Joao Seixas, Hiroaki Ohnishi, Pietro Cortese, 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), Tamás Csörgő, Gábor Dávid, Péter Lévai and Gábor Papp, 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, Meson production, Large Hadron Collider, 010308 nuclear & particles physics, Spectrum (functional analysis), Nuclear Theory, Inverse, 01 natural sciences, Nuclear physics, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, Production (computer science), 010306 general physics, Nuclear Experiment
Abstract

NA60; The NA60 experiment studied phi meson production in p-A and In-In collisions at the CERN SPS. The ratio phi/ω shows an increase by a factor not, vert, similar2 from peripheral to central collisions. The inverse slope parameter T of the pT spectrum increases with centrality, and seems to agree with the previous NA49 measurements.

Published
2005

50. J/$\psi$ production in indium-indium collisions at SPS energies

Author

L. Kluberg, A. Guichard, A. De Falco, P. Martins, Ruben Shahoyan, J. Lozano, A. Devaux, H. Gulkanian, Hiroaki Ohnishi, E. Radermacher, Laurent Ducroux, A. Neves, J. Castor, A. Colla, K. Banicz, P. Sonderegger, Corrado Cicalo, H. J. Specht, Alessandro Ferretti, M. Keil, S. Damjanovic, A. Drees, S. Serci, G. L. Usai, Roberta Arnaldi, P. Parracho, G. Puddu, P. Force, B. Chaurand, J. M. Heuser, Alberto Masoni, Michele Floris, Joao Seixas, P. Pillot, Pietro Cortese, R. Averbeck, P. Ramalhete, Chiara Oppedisano, N. Guettet, Carlos Lourenco, Rob Veenhof, H. En'yo, Raphael Noel Tieulent, Enrico Scomparin, A. David, Hermine Katharina Wöhri, Franck Manso, P. Rosinsky, 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), 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), NA60, 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), and Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Particle physics, Large Hadron Collider, Meson, Nuclear Theory, chemistry.chemical_element, 020206 networking & telecommunications, 02 engineering and technology, 7. Clean energy, Resonance (particle physics), Nuclear physics, Strange matter, chemistry, Quark–gluon plasma, 0202 electrical engineering, electronic engineering, information engineering, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], 020201 artificial intelligence & image processing, High Energy Physics::Experiment, Nucleon, Nuclear Experiment, Scaling, Indium
Abstract

NA60; The NA60 experiment collected data on dimuon production in indium-indium collisions at 158 GeV/c per incident nucleon, in year 2003, to contribute to the clarification of several questions raised by previous experiments studying high-energy heavy-ion physics at the CERN SPS in search of the quark gluon plasma. Among these previous results stands the observation, by NA50, that the production yield of J/psi mesons is suppressed in central Pb-Pb collisions beyond the normal nuclear absorption defined by proton-nucleus data. By comparing the centrality dependence of the suppression pattern between different colliding systems, S-U, Pb-Pb and In-In, we should be able to identify the corresponding scaling variable, and the physics mechanism driving the suppression. In this paper, we will present the ratio of J/psi and Drell-Yan production cross-sections in indium-indium collisions, in three centrality bins, and how these values compare to previous measurements. We will also present a study of the transverse momentum distributions of the J/psi mesons, in seven centrality bins.

Published
2005

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