Dilepton radiation and bulk viscosity in heavy-ion collisions

TL;DR

This paper studies how bulk viscosity influences thermal dilepton production and elliptic flow in heavy-ion collisions at RHIC and LHC energies, highlighting new calculations at LHC energies.

Contribution

It presents the first detailed calculation of bulk viscosity effects on dilepton elliptic flow at LHC energies, extending previous RHIC-focused studies.

Findings

Bulk pressure affects dilepton yield and flow at LHC energies.

Thermal dilepton $v_2$ is sensitive to both bulk and shear viscosities.

Results provide insights into the medium's transport properties in heavy-ion collisions.

Abstract

Starting from IP-Glasma initial conditions, we investigate the effects of bulk pressure on thermal dilepton production at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) energies. Though results of the thermal dilepton $v_2$ under the influence of both bulk and shear viscosity is presented for top RHIC energy, more emphasis is put on LHC energy where such a calculation is computed for the first time. The effects of the bulk pressure on thermal dilepton $v_2$ at the LHC are explored through bulk-induced modifications on the dilepton yield.