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arXiv · nucl-th/0203045

Nuclear absorption and $J/ψ$ suppression in Pb+Pb collisions

Abstract

We have analyzed the NA58 data on $J/ψ$ suppression in Pb+Pb collisions. $J/ψ$ production is assumed to be a two step process, (i) formation of $c\bar{c}$ pair, which is accurately calculable in QCD and (ii) formation of $J/ψ$ meson from the $c\bar{c}$ pair, which can be conveniently parameterized. In a pA/AA collision, a $c\bar{c}$ pair gain relative square momentum as it passes through the nuclear medium and some of the $c\bar{c}$ pairs can gain enough momentum to cross the threshold to become an open charm meson, leading to suppression in pA/AA collisions. A new prescription is proposed for the gain in momentum square, consistent with Krammer process. The model without any free parameter could explain the $E_T$ dependence of $J/ψ$ over Drell-Yan ratio.

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A. K. Chaudhuri. 2002-03-18. Nuclear absorption and $J/ψ$ suppression in Pb+Pb collisions. https://doi.org/10.1103/physrevc.66.021902

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