The STAR collaboration at the BNL Relativistic Heavy-Ion Collider (RHIC) reports measurements of the inclusive yield of nonphotonic electrons, which arise dominantly from semileptonic decays of heavy flavor mesons, over a broad range of transverse momenta (1.2<pT<10GeV/c) in p+p, d+Au, and Au+Au collisions at sNN=200GeV. The nonphotonic electron yield exhibits an unexpectedly large suppression in central Au+Au collisions at high pT, suggesting substantial heavy-quark energy loss at RHIC. The centrality and pT dependences of the suppression provide constraints on theoretical models of sup...
