Degrees of Freedom of the Quark Gluon Plasma, tested by Heavy Mesons

TL;DR

This paper investigates how different models of the Quark Gluon Plasma affect heavy quark energy loss, providing insights into the plasma's degrees of freedom through comparisons of model predictions.

Contribution

It compares various theoretical models to assess their sensitivity to the QGP's degrees of freedom and non-equilibrium effects on heavy quark energy loss.

Findings

Different models yield varying drag force predictions.

Heavy quark energy loss is highly sensitive to QGP properties.

Results help distinguish between models of QGP degrees of freedom.

Abstract

Heavy quarks (charm and bottoms) are one of the few probes which are sensitive to the degrees of freedom of a Quark Gluon Plasma (QGP), which cannot be revealed by lattice gauge calculations in equilibrium. Due to the rapid expansion of the QGP energetic heavy quarks do not come to an equilibrium with the QGP. Their energy loss during the propagation through the QGP medium depends strongly on the modelling of the interaction of the heavy quarks with the QGP quarks and gluons, i.e. on the assuption of the degrees of freedom of the plasma. Here we compare the results of different models, the pQCD based Monte-Carlo (MC@sHQ), the Dynamical Quasi Particle Model (DQPM) and the effective mass approach, for the drag force in a thermalized QGP and discuss the sensitivity of heavy quark energy loss on the properties of the QGP as well as on non-equilibrium dynamics