Speaker
Anthony Kesich
(University of California, Davis)
Description
Thermal suppression of quarkonium production in heavy-ion collisions, due to Debye screening of the quark-antiquark potential, has been proposed as a clear signature of quark-gluon plasma (QGP) formation. At RHIC energies, the \$Upsilon meson is a clean probe of the early system thanks to negligible levels of enhancement from b-bbar recombination and non-thermal suppression from co-mover absorption. We report on our measurement of the $\Upsilon \to e^+ e^-$ cross section for Au+Au collisions at $\sqrt{S_{NN}}$=200 GeV. We compute a Nuclear Modification Factor by comparing these results to newly analyzed p+p collisions from 2009 (21 pb^-1 compared to 7.9 pb^-1 in 2006). In order to have a complete assessment of both hot and cold nuclear matter effects on Upsilon production we also report on results from d+Au collisions.
Primary author
Anthony Kesich
(University of California, Davis)