System-size dependence of open-heavy-flavor production in nucleus-nucleus collisions at sNN =200 GeV

The PHENIX Collaboration at the Relativistic Heavy Ion Colliderhas measured open-heavy-flavor production in Cu + Cu collisionsat v root s(NN) = 200 GeV through the measurement of electrons at midrapidity that originate from semileptonic decaysof charm and bottom hadrons. In peripheral Cu + Cu collisionsan enhanced production of electrons is observed relative to p + p collisionsscaled by the number of binary collisions. In the transverse momentum range from 1 to 5 GeV/c the nuclear modification factor is R-AA similar to 1.4. As the system size increases to more central Cu + Cu collisions, the enhancement gradually disappears and turns into a suppression. For p(T) > 3 GeV/c, the suppression reaches R-AA similar to 0.8 in the most central collisions. The p(T) and centrality dependence of R-AA in Cu + Cu collisionsagree quantitatively with R-AA in d + Au and Au + Au collisions, if compared at a similar number of participating nucleons .