Charm elliptic flow in Au+Au collisions at RHIC
  Using the perturbative method for the simulation of charmed particles, the dynamical origin of charm quark elliptic flow is studied in the framework of a multi-phase transport (AMPT) model. Besides the expected ordering relative to that of light quarks according to quark masses, charm quark elliptic flow is seen to be sensitive to the parton scattering cross section. To describe the observed large elliptic flow of electrons from the decay of charmed mesons, a charm quark elastic scattering cross section much larger than that estimated from the perturbative QCD is required. 
Bin Zhang (Arkansas State U), Lie-Wen Chen (Shanghai Jiaotong U),   Che-Ming Ko (Texas A-M)