Abstract

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 ($1.2<{p}_{T}<10\text{ }\text{ }\mathrm{GeV}/c$) in $p+p$, $d+\mathrm{Au}$, and $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{{s}_{\mathrm{NN}}}=200\text{ }\text{ }\mathrm{GeV}$. The nonphotonic electron yield exhibits an unexpectedly large suppression in central $\mathrm{Au}+\mathrm{Au}$ collisions at high ${p}_{T}$, suggesting substantial heavy-quark energy loss at RHIC. The centrality and ${p}_{T}$ dependences of the suppression provide constraints on theoretical models of suppression.