Elliptic flow of identified hadrons in Au+Au collisions at √s_NN=200 GeV

Abstract

The anisotropy parameter (v₂), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at √s_NN=200 GeV for identified and inclusive charged particle production at central rapidities (|η|<0.35) with respect to the reaction plane defined at high rapidities (|η|=3-4 ). We observe that the v₂ of mesons falls below that of (anti)baryons for p_T>2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.