Azimuthal correlations of heavy quarks in Pb+Pb collisions at LHC ($\sqrt{s}=2.76$ TeV)

TL;DR

This study investigates how heavy quark pairs in Pb+Pb collisions at LHC are deflected and their azimuthal correlations broadened due to medium interactions, revealing momentum-dependent effects and differences between collisional and radiative energy loss mechanisms.

Contribution

It provides a detailed analysis of azimuthal correlation modifications of heavy quarks in heavy-ion collisions, highlighting the impact of different energy loss mechanisms and momentum classes.

Findings

Low-momentum pairs lose initial back-to-back correlation.

High-momentum pairs retain significant correlation.

Collisional energy loss broadens correlations more than radiative loss.

Abstract

In this paper we study the azimuthal correlations of heavy quarks in Pb+Pb collisions with $\sqrt{s}=2.76$ TeV at LHC. Due to the interaction with the medium heavy quarks and antiquarks are deflected from their original direction and the initial correlation of the pair is broadened. We investigate this effect for different transverse momentum classes. Low-momentum heavy-quark pairs lose their leading order back-to-back initial correlation, while a significant residual correlation survives at large momenta. Due to the larger acquired average deflection from their original directions the azimuthal correlations of heavy-quark pairs are broadened more efficiently in a purely collisional energy loss mechanism compared to including radiative corrections. This discriminatory feature survives when next-to-leading order production processes are included.