| Thème(s) : |
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Physique/Physique des Hautes Energies - Expérience
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| Titre : |
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Measurement of prompt and non-prompt J/psi production cross sections at mid-rapidity in pp collisions at \surd s = 7 TeV |
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| Auteur : |
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B. Abelev, L. Aphecetche1, A. Baldisseri2, G. Batigne1, I. Belikov3, A.A.E. Bergognon1, H. Borel2, M. Bregant1, J. Castillo Castellanos2, J.L. Charvet2, c. Cheshkov4, B. Cheynis4, H. Delagrange1, O. Driga1, L. Ducroux4, M. Estienne1, M. Germain1, J.-Y. Grossiord4, M. Guilbaud4, B. Hippolyte3, S. Jangal3, C. Kuhn3, A. Lardeux1, F. Lef'evre1, M. Lenhardt1, L. Luquin1, G. Martınez Garcıa1, A. Mas1, L. Massacrier1, 4, A. Matyja1, S. Pal2, H. Pereira Da Costa2, P. Pillot1, A. Rakotozafindrabe2, C. Roy3, X. Sanchez Castro3, Y. Schutz1, A. Shabetai1, D. Stocco1, R. Tieulent4, A. Uras4, R. Vernet5, R. Wan3, H. Yang2, Y. Zoccarato4, N. Arbor6, G. Conesa Balbastre6, J. Faivre6, C. Furget6, R. Guernane6, S. Kox6, J.S. Real6, C. Silvestre6, S.U. Ahn7, Y. .W. Baek7, A. Baldit7, V. Barret7, N. Bastid7, P. Crochet7, P. Dupieux7, R. Ichou7, X. Lopez7, F. Manso7, M. Marchisone7, S. Porteboeuf-Houssais7, P. Rosnet7, B. Vulpescu7, X. Zhang7 |
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| Laboratoire : |
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| équipe(s) de recherche : |
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Alice |
| Résumé : |
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The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at {\surd}s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L_int = 5.6nb-1. The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum pt > 1.3 GeV/c and rapidity |y| < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the Psi(2S) and Csi_c resonances, is sigma_prompt-J/psi(pt > 1.3 GeV/c, |y| < 0.9) = 7.2 +- 0.7(stat.) +- 1.0(syst.)+1.3-1.2 (syst.pol.) mb. The pt-differential cross section for prompt J/psi has also been measured. The cross section for the production of b-hadrons decaying to J/psi with transverse momentum greater than 1.3 GeV/c in the rapidity range |y| < 0.9 is sigma_{J/psi<-h_B} = 1.26 +- 0.33 (stat.) +0.23-0.28 (syst.) mb. The results are compared to QCD model predictions. The shape of the pt and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the bb pair total cross section and dsigma/dy at midrapidity. |
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| Collaboration/Projet : |
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ALICE |
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| Type de publication : |
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Articles dans des revues avec comité de lecture |
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Date de publication ou d'écriture : |
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2012 |
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| Nom du périodique : |
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| Journal of High Energy Physics |
| Publisher |
Institute of Physics (IOP) |
| ISSN |
1126-6708 (eISSN : 1029-8479) |
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| Volume : |
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2012 |
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| Page/Article : |
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065 |
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| Identifiant local : |
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LPSC12145 ; SUBATECH-Plasma |
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| Commentaire : |
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see paper for full list of authors |
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