Direct Photon Elliptic Flow at BNL Relativistic Heavy Ion Collider (RHIC) and CERN Large Hadron Collider (LHC)

TL;DR

This study employs event-by-event hydrodynamics with Glauber initial conditions to calculate thermal photon elliptic flow in heavy-ion collisions, revealing lower flow values than experimental reports from ALICE and PHENIX.

Contribution

It introduces a detailed hydrodynamical model incorporating spectral function and perturbative rates to compute photon elliptic flow in heavy-ion collisions.

Findings

Calculated photon elliptic flows are lower than experimental data.

Uses spectral function approach for hadronic phase photon rates.

Employs AMY perturbative rates for partonic phase photons.

Abstract

We use an event-by-event hydrodynamical description of the heavy-ion collision process with Glauber initial conditions to calculate the thermal emission of photons. The photon rates in the hadronic phase follow from a spectral function approach and a density expansion, while in the partonic phase they follow from the AMY perturbative rates. The calculated photon elliptic flows are lower than those reported recently by both the ALICE and PHENIX collaborations.