Estimation of electric conductivity of the quark gluon plasma via asymmetric heavy-ion collisions

TL;DR

This paper proposes a method to estimate the electric conductivity of the quark-gluon plasma by analyzing charge dipole deformations caused by electric fields in asymmetric heavy-ion collisions, especially Cu+Au.

Contribution

It introduces a novel approach using asymmetric collisions to probe the electric conductivity of the quark-gluon plasma through charge flow asymmetries.

Findings

Electric fields in asymmetric collisions induce charge dipoles.

Directed flow parameters are sensitive to charge dipoles.

Potential to measure quark-gluon plasma conductivity.

Abstract

We show that in asymmetric heavy-ion collisions, especially off-central Cu+Au collisions, a sizable strength of electric field directed from Au nucleus to Cu nucleus is generated in the overlapping region, because of the difference in the number of electric charges between the two nuclei. This electric field would induce an electric current in the matter created after the collision, which result in a dipole deformation of the charge distribution. The directed flow parameters $v_1^{\pm}$ of charged particles turn out to be sensitive to the charge dipole and provide us with information about electric conductivity of the quark gluon plasma.