Anisotropic flow generated by hard partons in medium

TL;DR

This paper demonstrates that energy and momentum deposition by hard partons in quark-gluon plasma creates streams that significantly influence flow anisotropies, affecting the interpretation of experimental data.

Contribution

It introduces a mechanism where hard partons generate streams in the plasma, contributing to flow anisotropies, and quantifies this effect using 3D hydrodynamic simulations.

Findings

Hard partons deposit energy and momentum into the plasma.

Generated streams contribute to flow anisotropies.

The mechanism affects the extraction of viscosity values.

Abstract

Hard partons which are produced copiously in nuclear collisions at the LHC, deposit most of their energy and momentum into the surrounding quark-gluon plasma. We show that this generates streams in the plasma and contributes importantly to flow anisotropies. With the help of event-by-event three-dimensional perfect hydrodynamic simulations we calculate the observable azimuthal anisotropies of hadronic distributions and show that the proposed mechanism is capable of generating non-negligible part of the observed signal. Hence, it must be taken into account in quantitative studies in which one tries to extract the values of viscosities from the comparison of simulated results with measured data.