Signs of Thermalization from RHIC Experiments

Selected results from the first five years of RHIC data taking are reviewed with emphasis on evidence for thermalization in central Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV.Comment: 10 pages, 6 figure

Inhomogeneous Shadowing Effects on J/\psi Production in dA Collisions

We study the effect of spatially homogeneous and inhomogeneous shadowing on $J/\psi$ production in deuterium-nucleus collisions. We discuss how the shadowing and its spatial dependence may be measured by comparing central and peripheral $dA$ collisions. These event classes may be selected by using gray protons from heavy ion breakup and events where the proton or neutron in the deuterium does not interact. We find that inhomogenous shadowing has a significant effect on central $dA$ collisions, larger than is observed in central $AA$ collisions. The inhomogeneity may be measured by comparing the rapidity dependence of $J/\psi$ production in central and peripheral collisions. Results are presented for $d$Au collisions at $\sqrt{s_{NN}} = 200$ GeV and $d$Pb collisions at $\sqrt{s_{NN}} = 6.2$ TeV.Comment: 10 pgs with 3 figure

Neutral Pion Distributions in PHENIX at RHIC

Transverse momentum spectra for identified $\pi^0$'s in the range 1 GeV/c $< p_T <$ 4 GeV/c have been measured by the PHENIX experiment in Au-Au collisions at $\sqrt{s}=130$ GeV. The spectra from peripheral nuclear collisions are consistent with the simple expectation of scaling the spectra from p+p collisions by the average number of nucleon-nucleon binary collisions. The spectra from central collisions and the ratio of central/peripheral spectra are significantly suppressed when compared to point-like scaling.Comment: 6 pages, 3 figure

ϕ\phi meson production in sNN\sqrt{s_{NN}} = 200 GeV Au+Au and pp collisions at RHIC

We present the results for the measurement of $\phi$ meson production in $\sqrt{s_{NN}}$ = 200 GeV Au+Au and pp collisions at the Relativistic Heavy Ion Collider (RHIC). Using the event mixing technique, spectra and yields are obtained from the $\phi\to K^{+}K^{-}$ decay channel for different centrality bins in Au+Au collisions and in pp collisions. We observe that the spectrum shape in Au+Au collisions depends weakly on the centrality and the shape of the spectrum in pp collisions is significantly different from that in Au+Au collisions. In Au+Au collisions, the extracted yield of $\phi$ meson is flat as a function of rapidity; The $$ of $\phi$, extracted from the fit function to the spectra, shows a different behavior as a function of centrality than that of $\pi^-$, $K^-$ and $\bar{p}$Comment: Proceedings for the 7th International Conference on Strangeness in Quark Matte

Heavy-flavour decay lepton measurements in pp, p-Pb, and Pb-Pb collisions with ALICE at the LHC

We present the measurements of electrons and muons from the semi-leptonic decays of heavy-flavour hadrons measured in the central and forward rapidity regions with ALICE in pp, Pb-Pb, and p-Pb, collisions at the LHC. The pT-differential production cross section in pp collisions, the elliptic flow in Pb-Pb collisions, and the nuclear modification factor in Pb-Pb and p-Pb collisions are shown. The results are compared to theoretical predictions.Comment: 8 pages, 6 figures, International Conference on the Initial Stages in High-Energy Nuclear Collisions (IS2013

Dielectron measurements in pp, p-Pb and Pb-Pb collisions with ALICE at the LHC

Electromagnetic probes are excellent messengers from the hot and dense medium created in high-energy heavy-ion collisions. Since leptons do not interact strongly, their spectra reflect the entire space-time evolution of the collision. The surrounding medium can lead to modifications of the dielectron production with respect to the vacuum rate. To quantify modifications in heavy-ion collisions, measurements in pp collisions serve as a reference, while the analysis of p-A collisions allows for the disentanglement of cold nuclear matter effects from those of the hot and dense medium. In this proceedings, dielectron measurements with the ALICE central barrel detectors are presented. The invariant mass distributions in the range $0<m_{ee}<3$ GeV/$c^{2}$ are compared to the expected yields from hadronic sources for pp collisions at $\sqrt{s}=7$ TeV, and for p-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. The cross section of direct photons measured via virtual photons in pp collisions is compared to predictions from NLO pQCD calculations as a function of the transverse momentum. The status of the analysis of Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV is presented.Comment: 4 pages, 8 figures, Proceedings of the "Quark Matter 2014 Conference", XXIV International Conference on Ultrarelativistic Nucleus-Nucleus Collisions, Darmstadt, May 19-24 201