$D\overline{D}$ momentum correlations versus relative azimuth as a sensitive probe for thermalization

TL;DR

This paper explores how Dar{D} meson momentum correlations versus azimuthal angle can serve as sensitive indicators of thermalization in quark-gluon plasma created during high-energy nuclear collisions at the LHC.

Contribution

It introduces a novel method using two-particle transverse momentum correlator to detect changes in heavy-quark azimuthal correlations as a sign of thermalization.

Findings

PYTHIA simulations for p-p collisions at 14 TeV show baseline correlations.

Radial flow effects are estimated to understand their impact.

The method could distinguish thermalized from non-thermalized states.

Abstract

In high-energy nuclear collisions at LHC, where a QGP might be created, the degree of thermalization at the partonic level is a key issue. Due to their large mass, heavy quarks are a powerful tool to probe thermalization. We propose to measure azimuthal correlations of heavy-quark hadrons and their decay products. Changes or even the complete absence of these initially existing azimuthal correlations in $Pb-Pb$ collisions might indicate thermalization at the partonic level. We present studies with PYTHIA for $p-p$ collisions at 14 TeV using the two-particle transverse momentum correlator ${<\overline{\Delta}p_{t,1}\overline{\Delta}p_{t,2}>}$ as a sensitive measure of potential changes in these azimuthal correlations. Contributions from transverse radial flow are estimated.