Gluon contribution to open heavy-meson production in heavy-ion collisions

TL;DR

This paper investigates how gluon-medium interactions affect open heavy-flavor meson production in heavy-ion collisions, revealing that gluon splitting significantly impacts production cross sections but has limited effect on nuclear modification due to short gluon lifetimes.

Contribution

It introduces a Langevin transport model that accounts for both collisional and radiative processes in gluon and heavy quark interactions within the QCD medium.

Findings

Gluon splitting significantly contributes to D meson production cross section.

Gluon-medium interactions have a modest effect on heavy meson nuclear modification.

Short gluon lifetimes limit the impact of gluon splitting on final heavy meson yields.

Abstract

A sizable contribution to heavy quark production in high-energy hadronic and nuclear collisions comes from heavy quark-antiquark pair production from gluon splitting during the parton shower evolution. We investigate the effect of gluon-medium interaction on open heavy flavor spectra in ultra-relativistic heavy-ion collisions. The interaction of hard gluons and heavy quarks with the hot QCD medium is simulated by utilizing a Langevin transport model that simultaneously incorporates contributions from collisional and radiative processes. It is found that while the gluon splitting channel has quite an important contribution to the single $D$ meson production cross section, its influence on the final heavy meson nuclear modification turns out to be quite modest because the average lifetime of hard gluons is short before splitting into heavy quark-antiquark pairs during the evolution and propagation of the parton shower.