Signatures of QCD conductivities in heavy-ion collisions

TL;DR

This paper investigates how QCD conductivities influence particle production in heavy-ion collisions, using hydrodynamic simulations with multiple conserved charges and lattice-QCD-based equations of state.

Contribution

It introduces a hydrodynamic model incorporating three diffusion currents with lattice-QCD-based equations of state to estimate rapidity distributions and constrain conductivities from experimental data.

Findings

Most conductivity matrix components can be constrained by experimental particle multiplicities.

Diffusive corrections significantly affect rapidity distributions.

Hydrodynamic evolution with multiple conserved charges provides insights into QCD transport properties.

Abstract

Dissipative processes are pivotal for understanding the hydrodynamic evolution of hot and dense QCD matter created in relativistic nuclear collisions. The interplay of multiple conserved charges -- net baryon, strangeness, and electric charge -- is of particular interest. We simulate the longitudinal hydrodynamic evolution with the three diffusion currents in a hydrodynamic model with a lattice-QCD-based equation of state, NEOS-4D, and estimate rapidity distributions including diffusive corrections to the phase-space distribution in the presence of multiple charges, which ensure charge conservation at particlization. We determine the response of particle yields at midrapidity to changes in the diagonal and off-diagonal conductivities. Inversely, we find that most components of the conductivity matrix can be constrained experimentally using identified particle multiplicities at different collision energies.