203 articles – 1878 Notices  [english version]
 HAL : in2p3-00137889, version 1
 arXiv : nucl-ex/0703033
 Physical Review Letters 99 (2007) 112301
 Partonic flow and $\phi$-meson production in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
 STAR Collaboration(s)
 (2007)
 We present first measurements of the $\phi$-meson elliptic flow ($v_{2}(p_{T})$) and high statistics $p_{T}$ distributions for different centralities from $\sqrt{s_{NN}}$ = 200 GeV Au+Au collisions at RHIC. In minimum bias collisions the $v_{2}$ of the $\phi$ meson is consistent with the trend observed for mesons. The ratio of the yields of the $\Omega$ to those of the $\phi$ as a function of transverse momentum is consistent with a model based on the recombination of thermal $s$ quarks up to $p_{T}\sim 4$ GeV/$c$, but disagrees at higher momenta. The nuclear modification factor ($R_{CP}$) of $\phi$ follows the trend observed in the $K^{0}_{S}$ mesons rather than in $\Lambda$ baryons, supporting baryon-meson scaling. Since $\phi$-mesons are made via coalescence of seemingly thermalized $s$ quarks in central Au+Au collisions, the observations imply hot and dense matter with partonic collectivity has been formed at RHIC.
 Thème(s) : Physique/Physique Nucléaire Expérimentale
 Lien vers le texte intégral : http://fr.arXiv.org/abs/nucl-ex/0703033
 in2p3-00137889, version 1 http://hal.in2p3.fr/in2p3-00137889 oai:hal.in2p3.fr:in2p3-00137889 Contributeur : Dominique Girod <> Soumis le : Jeudi 22 Mars 2007, 14:22:57 Dernière modification le : Mardi 18 Septembre 2007, 10:40:56