Abstract : 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.
http://hal.in2p3.fr/in2p3-00630071
Contributeur : Dominique Girod <>
Soumis le : vendredi 7 octobre 2011 - 10:57:27
Dernière modification le : mercredi 27 juillet 2016 - 14:48:48
G. Agakishiev, M. M. Aggarwal, Z. Ahammed, A.V. Alakhverdyants, I. Alekseev, et al.. Identified hadron compositions in p+p and Au+Au collisions at high transverse momenta at $\sqrt{s_{_{NN}}} = 200$ GeV. Physical Review Letters, American Physical Society, 2012, 108, pp.072302. <10.1103/PhysRevLett.108.072302>. <in2p3-00630071>
