Heavy-flavour spectra in high energy nucleus-nucleus collisions

TL;DR

This paper models heavy quark propagation in high-energy nucleus-nucleus collisions using Langevin dynamics within hydrodynamic backgrounds, providing insights into their spectra and flow characteristics.

Contribution

It introduces a combined approach using Langevin dynamics and hydrodynamics with evaluated transport coefficients to study heavy-flavour observables.

Findings

Calculated heavy-quark spectra and R_AA agree with experimental data.

Predicted elliptic flow v_2 of heavy-flavour decay electrons.

Provided a framework for understanding heavy-quark energy loss and flow in quark-gluon plasma.

Abstract

The propagation of the heavy quarks produced in relativistic nucleus-nucleus collisions at RHIC and LHC is studied within the framework of Langevin dynamics in the background of an expanding deconfined medium described by ideal and viscous hydrodynamics. The transport coefficients entering into the relativistic Langevin equation are evaluated by matching the hard-thermal-loop result for soft collisions with a perturbative QCD calculation for hard scatterings. The heavy-quark spectra thus obtained are employed to compute the differential cross sections, the nuclear modification factors R_AA and the elliptic flow coefficients v_2 of electrons from heavy-flavour decay.