HAL : in2p3-00630071, version 1
 arXiv : 1110.0579
 Physical Review Letters 108 (2012) 072302
 Identified hadron compositions in p+p and Au+Au collisions at high transverse momenta at $\sqrt{s_{_{NN}}} = 200$ GeV
 STAR Collaboration(s)
 (2012)
 We report transverse momentum ($p_{T} \leq15$ GeV/$c$) spectra of $\pi^{\pm}$, $K^{\pm}$, $p$, $\bar{p}$, $K_{S}^{0}$, and $\rho^{0}$ at mid-rapidity in p+p and Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV. Perturbative QCD calculations are consistent with $\pi^{\pm}$ spectra in p+p collisions but do not reproduce $K$ and $p(\bar{p})$ spectra. The observed decreasing antiparticle-to-particle ratios with increasing $p_T$ provide experimental evidence for varying quark and gluon jet contributions to high-$p_T$ hadron yields. The relative hadron abundances in Au+Au at $p_{T}{}^{>}_{\sim}8$ GeV/$c$ are measured to be similar to the p+p results, despite the expected Casimir effect for parton energy loss.
 Thème(s) : Physique/Physique Nucléaire Expérimentale
 Lien vers le texte intégral : http://fr.arXiv.org/abs/1110.0579
 in2p3-00630071, version 1 http://hal.in2p3.fr/in2p3-00630071 oai:hal.in2p3.fr:in2p3-00630071 Contributeur : Dominique Girod <> Soumis le : Vendredi 7 Octobre 2011, 10:57:27 Dernière modification le : Vendredi 4 Mai 2012, 14:34:29