We report the beam energy ( √ sNN = 7.7 -200 GeV) and collision centrality dependence of the mean (M ), standard deviation (σ), skewness (S), and kurtosis (κ) of the net-proton multiplicity distributions in Au+Au collisions. The measurements are carried out by the STAR experiment at midrapidity (|y| < 0.5) and within the transverse momentum range 0.4 < pT < 0.8 GeV/c in the first phase of the Beam Energy Scan program at the Relativistic Heavy Ion Collider. These measurements are important for understanding the Quantum Chromodynamic (QCD) phase diagram.

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Posterior distributions for physical parameters describing relativistic heavy-ion collisions, such as the viscosity of the quark-gluon plasma, are extracted through a comparison of hydrodynamicbased transport models to experimental results from 100A GeV + 100A GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). By simultaneously varying six parameters and by evaluating several classes of observables, we are able to explore the complex intertwined dependencies of observables on model parameters. The methods proved a full multi-dimensional posterior distribution for the model output, including a range of acceptable values for each parameter, and reveal correlations between them. The breadth of observables and the number of parameters considered here go beyond previous studies in this field. The statistical tools, which are based upon Gaussian Process emulators, are tested in detail and should be extendable to larger data sets and a higher number of parameters.

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We report measurements of charmed-hadron (D 0 , D * ) production cross sections at mid-rapidity in p + p collisions at a center-of-mass energy of 200 GeV by the STAR experiment. Charmed hadrons were reconstructed via the hadronic decaysand their charge conjugates, covering the pT range of 0.6−2.0 GeV/c and 2.0−6.0 GeV/c for D 0 and D * + , respectively. From this analysis, the charm-pair production cross section at mid-rapidity is dσ/dy| cc y=0 = 170 ± 45 (stat.) +38 −59 (sys.) µb. The extracted charm-pair cross section is compared to perturbative QCD calculations. The transverse momentum dierential cross section is found to be consistent with the upper bound of a Fixed-Order Next-to-Leading Logarithm calculation.

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Rapidity-odd directed flow (v1) measurements for charged pions, protons and antiprotons near mid-rapidity (y = 0) are reported in

Local parity-odd domains are theorized to form inside a Quark-Gluon-Plasma (QGP) which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect (CME). The experimental observation of charge separation has previously been reported for heavy-ion collisions