Partonic flow and ϕ-meson production in Au+Au collisions at VsNN=200 = GeV

Abstract

We present first measurements of the ϕ-meson elliptic flow (v2(pT)) and high-statistics pT distributions for different centralities from √sNN=200 GeV Au+Au collisions at RHIC. In minimum bias collisions the v2 of the ϕ meson is consistent with the trend observed for mesons. The ratio of the yields of the Ω to those of the ϕ as a function of transverse momentum is consistent with a model based on the recombination of thermal s quarks up to pT∼4 GeV/c, but disagrees at higher momenta. The nuclear modification factor (RCP) of ϕ follows the trend observed in the KS0 mesons rather than in Λ baryons, supporting baryon-meson scaling. These data are consistent with ϕ mesons in central Au+Au collisions being created via coalescence of thermalized s quarks and the formation of a hot and dense matter with partonic collectivity at RHIC.