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Abstract

J/\psi suppression has long been considered a sensitive signature of the formation of the Quark-Gluon Plasma (QGP) in relativistic heavy-ion collisions. In this letter, we present the first measurement of inclusive J/\psi production at mid-rapidity through the dimuon decay channel in Au+Au collisions at \sqrt{s_{NN}} = 200 GeV with the STAR experiment. These measurements became possible after the installation of the Muon Telescope Detector was completed in 2014. The J/\psi yields are measured in a wide transverse momentum (p_{\rm{T}}) range of 0.15 GeV/c to 12 GeV/c from central to peripheral collisions. They extend the kinematic reach of previous measurements at RHIC with improved precision. In the 0-10% most central collisions, the J/\psi yield is suppressed by a factor of approximately 3 for p_{\rm{T}}>5 GeV/c relative to that in p+p collisions scaled by the number of binary nucleon-nucleon collisions. The J/\psi nuclear modification factor displays little dependence on p_{\rm{T}} in all centrality bins. Model calculations can qualitatively describe the data, providing further evidence for the color-screening effect experienced by J/\psi mesons in the QGP.