Nuclear modification factor of nonphotonic electrons in heavy-ion collisions, and the heavy-flavor baryon-to-meson ratio

The nuclear modification factor RAA of nonphotonic electrons in Au + Au collisions at √sNN = 200 GeV is studied by considering the decays of heavy-flavor hadrons produced in a quark coalescence model. Although an enhanced c/D ratio is predicted by the coalescence model, it is peaked at small transverse momenta (∼2 GeV) due to the large difference between heavy and light quark masses. As a result, the enhanced c/D ratio, which is expected to suppress the electron RAA as the branching ratio of c decay into electrons is smaller than that of D0, does not lead to additional suppression of the electron RAA at large transverse momenta ( 5 GeV), where the suppression is mainly due to heavy quark energy loss in produced quark-gluon plasma. Also, the enhanced b/B̄ ratio predicted by the coalescence model has even smaller effect on the nonphotonic electron RAA as bottom baryons and mesons have similar branching ratios for semileptonic decays into electrons.