Multiplicity density at mid-rapidity in $AA$ collisions: effect of meson cloud

TL;DR

This paper investigates how the meson cloud of nucleons affects charged particle multiplicity predictions in heavy-ion collisions, showing a significant increase in multiplicity density and a reduction in the needed binary collision fraction.

Contribution

It introduces the impact of the meson cloud into the Monte Carlo Glauber model, providing more accurate predictions for heavy-ion collision outcomes.

Findings

Meson cloud increases multiplicity density by 16-18% in central AA collisions.

Meson-baryon Fock component reduces the binary collision fraction needed.

Significant impact observed at both RHIC and LHC energies.

Abstract

We study the influence of the meson cloud of the nucleon on predictions of the Monte Carlo Glauber model for the charged particle multiplicity density at mid-rapidity in $AA$ collisions. We find that for central $AA$ collisions the meson cloud can increase the multiplicity density by $\sim 16-18$\%. The meson-baryon Fock component reduces the required fraction of the binary collisions by a factor of $\sim 2$ for Au+Au collisions at $\sqrt{s}=0.2$ TeV and $\sim 1.5$ for Pb+Pb collisions at $\sqrt{s}=2.76$ TeV.