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arXiv · 1408.4756

Enhanced production of $ψ(2S)$ mesons in heavy ion collisions

Sungtae Cho
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Abstract

We study the production of a $ψ(2S)$ meson in heavy ion collisions. We evaluate Wigner functions for the $ψ(2S)$ meson using both Gaussian and Coulomb wave functions, and investigate the wave function dependence in the $ψ(2S)$ meson production by recombination of charm and anti-charm quarks. The enhanced transverse momentum distribution of $ψ(2S)$ mesons compared to that of $J/ψ$ mesons, originated from wave function distributions of the $ψ(2S)$ and $J/ψ$ meson in momentum space, provides a plausible explanation for the recent measurement of the nuclear modification factor ratio between the $ψ(2S)$ and $J/ψ$ meson.

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Sungtae Cho. 2014-08-20. Enhanced production of $ψ(2S)$ mesons in heavy ion collisions. https://doi.org/10.1103/physrevc.91.054914

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