Measurements of Open Heavy Flavor Production in Semi-leptonic Channels at STAR

Abstract

In these proceedings, we present the most recent results on Non-Photonic Electron (NPE) production from semi-leptonic decays of open heavy flavor hadrons with the STAR experiment at the Relativistic Heavy Ion Collider. We first report the updated results on NPE production in p+p collsions at sNN=200 GeV with much improved precision and wider kinematic coverage than previous ones. The nuclear modification factor RAA obtained with this new p+p reference in most central Au+Au collisions at sNN=200 GeV shows significant suppression at high pT, while the suppression reduces gradually towards more peripheral collisions. We also report new RAA results for NPE production in the 0–5% most central U+U collisions at sNN=193 GeV and compare with those in Au+Au collisions at sNN=200 GeV Calculations suggest that a 20% higher Bjorken energy density may be reached in U+U collisions, which can lead to a stronger suppression of NPE production. We find that the RAA in U+U collisions is systematically lower than that in 0–5% centrality Au+Au collisions, but still consistent within uncertainty. Finally we report the most recent development in measurements of NPE from open bottom and charm hadron decays separately, utilizing the new Heavy Flavor Tracker of the STAR experiment.