اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدPartonic flow and $phi$-meson production in Au+Au collisions at $sqrt{s_{NN}}$ = 200 GeV
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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.
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