Directed flow of open charm in Au+Au collisions atsNN=200GeV using a quark coalescence model

Abstract

The directed flow ($v_{1}$) of open charm meson ($D^{0}$) is studied in Au+Au collisions at $\sqrt{s_{NN}}$ = 200~GeV using A Multi-Phase Transport (AMPT) model framework with partonic interactions (string melting version). Within this framework, it is found that although the initial spatial eccentricity ($\epsilon_{1}$) of charm quark is smaller than light quarks, the charm quark $v_{1}$ magnitude is found to be approximately 7 times larger than that of the light u quark at large rapidity. This indicates that the charm quarks can retain more information from initial condition than the light quarks. We have studied the directed flow of $D^{0}$ as a function of rapidity and transverse momentum using quark coalescence as the mechanism for hadron production. Like charm quark, the $D^{0}$ $v_{1}$ magnitude is found to be about 7 times larger than that of the light ($\pi$) hadrons at large rapidity.