Multiscale evolution of heavy flavor in the QGP

TL;DR

This paper investigates the multiscale evolution of heavy flavor jets in the quark-gluon plasma, focusing on mass effects during different virtuality stages, and employs realistic simulations to compare heavy and light quark energy loss.

Contribution

It introduces a comprehensive multiscale framework for heavy flavor jet evolution in the QGP, including virtuality-dependent radiation, scattering, and pair production mechanisms.

Findings

Heavy flavor mass modifies gluon emission during high virtuality stages.

Differences in energy loss mechanisms between heavy and light quarks are quantified.

Dynamical pair production of heavy flavor significantly impacts jet evolution.

Abstract

Shower development dynamics for a jet traveling through the quark-gluon plasma (QGP) is a multiscale process, where the heavy flavor mass is an important scale. During the high virtuality portion of the jet evolution in the QGP, emission of gluons from a heavy flavor is modified owing to heavy quark mass. Medium-induced radiation of heavy flavor is sensitive to microscopic processes (e.g. diffusion), whose virtuality dependence is phenomenologically explored in this study. In the lower virtuality part of shower evolution, i.e. when the mass is comparable to the virtuality of the parton, scattering and radiation processes of heavy quarks differ from light quarks. The effects of these mechanisms on shower development in heavy flavor tagged showers in the QGP is explored here. Furthermore, this multiscale study examines dynamical pair production of heavy flavor (via virtual gluon splittings) and their subsequent evolution in the QGP, which is not possible otherwise. A realistic event-by-event simulation is performed using the JETSCAPE framework. Energy-momentum exchange with the medium proceeds using a weak coupling recoil approach. Using leading hadron and open heavy flavor observables, differences in heavy versus light quark energy-loss mechanisms are explored, while the importance of heavy flavor pair production is highlighted along with future directions to study.