First measurement of J/ψ anisotropy by PHENIX experiment at RHIC

Understanding the J/ψ suppression and possible recombination mechanisms at RHIC is one of the outstanding challenges for theorists and experimentalists. Recent results provided by PHENIX showed a stronger suppression at forward rapidity, while at mid-rapidity the suppression is similar to lower energy collision experiments. A large sample of Au + Au collisions at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \sqrt {s_{NN} } $$\end{document} = 200 GeV was collected in 2007 with the PHENIX experiment at RHIC. Using this sample, J/ψs were identified in the di-electron decay channel. In order to probe the charm coalescence as an additional J/ψ production mechanism at RHIC, we studied the first determination of its v2 elliptic flow parameter at mid-rapidity.