Nuclear modification of $B_c$ mesons in relativistic heavy-ion collisions based on a linear Boltzmann transport model

TL;DR

This study investigates how $B_c$ mesons are modified in high-energy nuclear collisions using a linear Boltzmann transport model, revealing the dominant production mechanisms and the impact of medium interactions.

Contribution

It introduces a comprehensive transport model incorporating both Yukawa and string interactions to study $B_c$ meson behavior in quark-gluon plasma, providing new insights into their production and suppression mechanisms.

Findings

Most primordial $B_c$ mesons dissociate in QGP.

Recombination dominates at low transverse momentum, fragmentation at high.

String interaction has a greater impact than Yukawa in $B_c$ modification.

Abstract

The nuclear modification factor ($R_\mathrm{AA}$) of $B_c$ mesons in high-energy nuclear collisions provides a novel probe of heavy quark interactions with the quark-gluon plasma (QGP). Based on a linear Boltzmann transport model that incorporates both Yukawa and string types of interactions between heavy quarks and the QGP, we study the production and evolution of heavy quarks and $B_c$ mesons within the same framework. A $B_c$ bound state dissociates while one of its constituent heavy quarks scatters with the QGP with momentum transfer greater than its binding energy. The medium-modified charm and bottom quarks can recombine into $B_c$ mesons, and the medium-modified bottom quarks can also fragment to $B_c$ mesons. We find that most primordial $B_c$ mesons generated from the initial hard collisions dissociate inside the QGP. The production of $B_c$ mesons is primarily driven by the recombination mechanism at low transverse momentum and fragmentation at high transverse momentum. The string interaction dominates over the Yukawa interaction in the nuclear modification of $B_c$ mesons. The participant number dependence of the $B_c$ meson $R_\mathrm{AA}$ is determined by the complicated interplay between the heavy quark yield, energy loss, and the QGP volume. We obtain a reasonable description of the $R_\mathrm{AA}$ of $B_c$ mesons in Pb+Pb collisions at $\sqrt{s_\mathrm{NN}}=5.02$ TeV, and provide predictions for Au+Au collisions at $\sqrt{s_\mathrm{NN}}=200$ GeV.