Measurements of midrapidity charged particle multiplicity distributions, dN ch /dη, and midrapidity transverse-energy distributions, dET /dη, are presented for a variety of collision systems and energies. Included are distributions for Au+Au collisions at For all A+A collisions down to √ s N N = 7.7 GeV, it is observed that the midrapidity data are better described by scaling withNqp than scaling with Npart. Also presented are estimates of the Bjorken energy density, εBJ, and the ratio of dET /dη to dN ch /dη, the latter of which is seen to be constant as a function of centrality for all systems.

identified hadrons π ± , K ± , p, andp produced at midrapidity in Cu+Au collisions at

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The PHENIX Collaboration at the Relativistic Heavy Ion Collider has measured open heavy flavor production in minimum bias Au+Au collisions at √ s N N = 200 GeV via the yields of electrons from semileptonic decays of charm and bottom hadrons. Previous heavy flavor electron measurements indicated substantial modification in the momentum distribution of the parent heavy quarks due to the quark-gluon plasma created in these collisions. For the first time, using the PHENIX silicon vertex detector to measure precision displaced tracking, the relative contributions from charm and bottom hadrons to these electrons as a function of transverse momentum are measured in Au+Au collisions. We compare the fraction of electrons from bottom hadrons to previously published results extracted from electron-hadron correlations in p+p collisions at √ s N N = 200 GeV and find the fractions to be similar within the large uncertainties on both measurements for pT > 4 GeV/c. We use the bottom electron fractions in Au+Au and p+p along with the previously measured heavy flavor electron RAA to calculate the RAA for electrons from charm and bottom hadron decays separately. We find that electrons from bottom hadron decays are less suppressed than those from charm for the region 3 < pT < 4 GeV/c.