# Diffusion of charm quarks in jets in high-energy heavy-ion collisions

## TL;DR

This paper investigates how charm quarks diffuse within jets in high-energy heavy-ion collisions using a Monte Carlo transport model, revealing significant diffusion effects at low transverse momentum and providing predictions for future experimental comparisons.

## Contribution

It introduces a detailed Monte Carlo transport model incorporating NLO+PS event generation and both elastic and inelastic interactions to study charm quark diffusion in jets.

## Key findings

- Radial distribution of $D^0$ mesons shifts outward at low $p_T$ indicating strong diffusion.
- Angular deviation of charm quarks decreases with increasing $p_T$ and is more sensitive to collisional interactions.
- Predictions for $D^0$ meson distributions and nuclear modification factors at RHIC and LHC energies.

## Abstract

The radial distribution of $D^0$ mesons in jets probes the diffusion of charm quark relative to the jet axis and provides a new perspective to study the interaction mechanisms between heavy quarks and the medium in the nucleus-nucleus collisions. The in-medium parton propagations are described by a Monte Carlo transport model which uses the next-to-leading order (NLO) plus parton shower (PS) event generator SHERPA as input and includes elastic (collisional) and inelastic (radiative) interaction for heavy quarks as well as light partons. At low $D^0$ meson $p_T$, the radial distribution significantly shifts to larger radius indicating a strong diffusion effect which is consistent with the recent experimental data. We demonstrate that the angular deviation of charm quarks declines with $p_T$ and is very sensitive to the collisional more than radiative interaction at $p_T<5$~GeV. As predictions, we present the $D^0$ meson radial distribution in jets in p+p and $0-10\%$ Au+Au collisions at $\sqrt{s_{NN}}=200$~GeV at the RHIC, and also estimate the nuclear modification factor of charm jet in central Au+Au collisions at 200~GeV at the RHIC and central Pb+Pb collisions at $5.02$~TeV at the LHC.