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arXiv · 1109.3891

Measuring the Upsilon Nuclear Modification Factor at STAR

Rosi Reed
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Abstract

Suppression of quarkonia in heavy ion collisions with respect to proton-proton collisions due to the Debye screening of the potential between the heavy quarks was hypothesized to be a signature of the Quark Gluon Plasma (QGP). However, other effects besides Debye screening, such as the statistical recombination of quark anti-quark heavy flavor pairs, or co-mover absorption can also affect quarkonia production in heavy ion collisions. Quantifying the suppression of an entire family of quarkonium mesons can give us a model dependent constraint on the temperature. The suppression of Upsilon can be quantified by calculating the Nuclear Modification factor, RAA, which is the ratio of the production in Au+Au collisions to the production in p+p scaled by the number of binary collisions. We present our results for mid-rapidity Upsilon(1S+2S+3S) production in p+p and Au+Au collisions at sqrt(sNN) = 200 GeV. The centrality dependence of RAA will be shown for the combined Upsilon(1S+2S+3S) yield.

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Rosi Reed. 2011-09-18. Measuring the Upsilon Nuclear Modification Factor at STAR. https://doi.org/10.1088/0954-3899%2F38%2F12%2F124185

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