J/ψ\psi polarization in p+p collisions at s\sqrt{s} = 200 GeV in STAR

In this paper, J/$\psi$ polarization at mid-rapidity in $p+p$ collisions at $\sqrt{s}$ = 200 GeV measured in the STAR experiment at RHIC is reported. J/$\psi$ production is analyzed via the dielectron decay channel. J/$\psi$ polarization is extracted from the decay angular distribution in the helicity frame. The J/$\psi$ polarization is measured at transverse momentum range (2 - 6) GeV/c and is found to be consistent with $NLO^+$ Color Singlet Model ($NLO^+$ CSM), Color Octet Model (COM) predictions and with no polarization within current uncertainties.Comment: 6 pages, 4 figure, Proceedings of the International Conference on Strangeness in Quark Matter 2011 (SQM2011), Krakow, Poland, September 18-24, 201

Quarkonia production in the STAR experiment

In this paper, we highlight recent STAR J/ψ and ϒ results. J/ψ nuclear modification factors (RAA) in Au+Au collisions at √sNN = 200, 62.4 and 39 GeV and in U+U collisions at √sNN = 193 GeV, ϒ RAA in d+Au and Au+Au collisions at √sNN = 200 and in U+U collisions at √sNN = 193 GeV are measured and compared to different theoretical calculations. We also report J/ψ elliptic flow (v2) results in Au+Au collisions at √sNN = 200 GeV and the first ψ(2S) to J/ψ ratio measurement in p + p collisions at √s = 500 GeV