STAR Measurements of Bottom to Charm Ratio and Heavy Quark Interaction   with the QCD Medium through Non-Photonic Electron-Hadron Correlations
  We present STAR measurements of relative charm and bottom contributions to NPE from $p+p$ collisions at $\sqrt{s}$= 200 and 500 GeV energies. We report the total bottom quark production cross section from p+p collisions at $\sqrt{s}= 200$ GeV extracted from NPE spectrum and B to D ratios. We also present the NPE-hadron azimuthal correlations from $Au+Au$ collisions at $\sqrtsNN = 200$ GeV from the 2010 RHIC run where we have collected high statistics data set with low photonic conversion background. 
Wenqin Xu (for the STAR Collaboration)
nucl-ex hep-ex