System size dependence of energy loss and correlations of heavy mesons at LHC energies

TL;DR

This study investigates how the size of the collision system at LHC energies affects heavy quark energy loss and correlations, providing insights into the underlying QGP interactions and hadronization processes.

Contribution

It offers a detailed analysis of system size effects on heavy quark observables using the EPOS4HQ model across various collision systems, highlighting new ways to probe QGP properties.

Findings

System size influences heavy quark momentum loss.

Heavy baryon production is enhanced at low transverse momentum.

Azimuthal correlations reveal details of heavy quark production mechanisms.

Abstract

We study the system size dependence of heavy quark (HQ) observables at a center of mass energy of $\sqrt{s_{\rm NN}}=5.02$ TeV to explore whether it can provide further constraints on the physical processes which are involved: energy loss of HQs in the quark gluon plasma (QGP), hadronization and hadronic rescattering. We use the EPOS4HQ approach to study p-p and 0-10\% central O-O, Ar-Ar, Kr-Kr and Pb-Pb reactions and investigate in detail the momentum change of heavy quarks from creation until their detection as part of a hadron as well as the enhancement of heavy baryon production at low $p_T$. We investigate furthermore the origin and the system size dependence of the azimuthal correlations between the heavy quark $Q$ and the heavy antiquark $\bar Q$ and how one can bypass the problem that correlations are washed out due to the combinatorial background. We conclude that a systematic study of the system size dependence of the momentum loss allows to separate the momentum loss due to the passage through the QGP from the momentum change due to hadronization and the $Q\bar Q$ correlations allow to gain inside into the different pQCD processes in which the heavy quarks are created.