Event-plane decorrelation of photons produced in the early stage of heavy-ion collisions

TL;DR

This paper investigates the early-stage photon production in heavy-ion collisions, focusing on event-plane decorrelation to understand the complex pre-hydrodynamics phase and its potential as a dynamical probe.

Contribution

It introduces a multistage model combining IP-Glasma, K exto{}MP exto{}ST, and hydrodynamics to analyze photon anisotropy and decorrelation.

Findings

Photon-hadron event-plane decorrelation is significant in early photons.

Early photons exhibit small momentum anisotropy.

Decorrelations can reveal information about pre-hydrodynamics phase.

Abstract

We study photon production in the early stage of heavy-ion collisions using a multistage model combining IP-Glasma, K\o{}MP\o{}ST and relativistic hydrodynamics. We discuss the small momentum anisotropy of these photons, highlighting the role of the photon-hadron event-plane decorrelation. We comment that this singular characteristic of early photons could be used to provide dynamical information on the complex pre-hydrodynamics phase of heavy-ion collisions.