Heavy-quark production and elliptic flow in Au + Au collisions at sNN =62.4 GeV

We present measurements of electrons and positrons from the semileptonic decaysof heavy- flavorhadrons at midrapidity (|y|< 0.35) in Au+Au collisions at sNN−−−−√=62.4 GeV. The data were collected in 2010 by the PHENIX experiment that included the new hadron-blind detector. The invariant yield of electrons from heavy- flavordecays is measured as a function of transverse momentum in the range 1 flavordecays is nonzero when averaged between 1.3 flavordecays at sNN−−−−√=200 GeV. The v2 of the electrons from heavy- flavordecay at the lower beam energy is also smaller than v2 for pions. Both results indicate that the heavy quarks interact with the medium formed in these collisions, but they may not be at the same level of thermalization with the medium as observed at sNN−−−−√=200 GeV.