Non-equilibrium evolution of quarkonium in medium in the open quantum system approach

TL;DR

This paper reviews recent advances in modeling bottomonium behavior in quark-gluon plasma using an open quantum system approach, incorporating effective field theory and hydrodynamics to match experimental observations.

Contribution

It introduces a systematic framework combining pNRQCD and open quantum systems to describe bottomonium evolution in medium at NLO accuracy.

Findings

NLO OQS+pNRQCD predicts bottomonium suppression consistent with LHC data.

The approach captures elliptic flow of bottomonium in heavy-ion collisions.

Comparisons show good agreement with experimental results using realistic initial conditions.

Abstract

In this proceedings contribution, I review recent work that aims to provide a more comprehensive and systematic understanding of bottomonium dynamics in the quark-gluon plasma using an open quantum system (OQS) approach that is applied in the framework of the potential non-relativistic QCD (pNRQCD) effective field theory and coupled to realistic hydrodynamical backgrounds that have been tuned to soft hadron observables. I review how the computation of bottomonium suppression can be reduced to solving a Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) equation for the evolution of the b-bbar reduced density matrix, which includes both singlet and octet states plus medium-induced transitions between them at next-to-leading order (NLO) in the binding energy over temperature. Finally, I present comparisons of phenomenological predictions of the NLO OQS+pNRQCD approach and experimental data for bottomonium suppression and elliptic flow in LHC 5.02 TeV Pb-Pb collisions obtained using both smooth and fluctuating hydrodynamic initial conditions.