Toward an understanding of the RAA and v2 puzzle for heavy quarks

We discuss how the temperature dependence of the heavy quark drag coefficient can address for a large part of such a puzzle. We have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP). All the four different models are set to reproduce the same RAA(pT) experimentally observed at RHIC energy. We have found that for the same RAA(pT) one can generate 2-3 times more v2 depending on the temperature dependence of the heavy quark drag coefficient.