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

TL;DR

This paper investigates the production mechanisms of $ ext{psi}(2S)$ mesons in heavy ion collisions, focusing on wave function effects and their impact on observed nuclear modification factors.

Contribution

It introduces a detailed analysis of $ ext{psi}(2S)$ production using Wigner functions with different wave functions, highlighting wave function dependence in recombination models.

Findings

Enhanced transverse momentum distribution of $ ext{psi}(2S)$ compared to $J/ ext{psi}$

Wave function distributions influence meson production and momentum spectra

Provides explanation for the nuclear modification factor ratio measurements

Abstract

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