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Effects of Multiple Scattering in Cold Nuclear Matter on J/psi Suppression and in Heavy Ion Collisions

A. M. Glenn·Denes Molnar·J. L. Nagle
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Abstract

Coherent multiple scatterings of c and cbar quark pairs in the environment of heavy ion collisions have been used in a previous work by Qiu et al. [Qiu:1998rz] to study J/psi suppression. That model suggests that heavy quark re-scatterings in a cold nuclear medium can completely explain the centrality dependence of the observed J/psi suppression in Pb+Pb collisions at the SPS [Abreu:2001kd]. Their calculations also revealed significant differences under the assumptions of a color singlet or color octet production mechanism. A more recent analytic calculation [Fujii:2003fq], which includes incoherent final-state re-scatterings with explicit momentum transfer fluctuations in three dimensions, indicates much less suppression and little sensitivity to the production mechanism. In this article, we study simultaneously both the J/psi suppression and p_T modifications, at SPS and RHIC energies. We mainly focus on incoherent momentum transfer fluctuations in two dimensions, which is more appropriate for the heavy-ion collision kinematics. Our analytic and Monte-Carlo calculations reinforce the analytic results in [Fujii:2003fq]. Additionally, we find that the experimental J/psi suppression and from nucleus-nucleus collisions at the SPS or RHIC cannot simultaneously be described in this incoherent multiple scattering framework for any value of the fluctuation strength parameter .

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A. M. Glenn, Denes Molnar, J. L. Nagle. 2006-11-01. Effects of Multiple Scattering in Cold Nuclear Matter on J/psi Suppression and in Heavy Ion Collisions. https://doi.org/10.1016/j.physletb.2006.10.069

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