The weak magnetic field effect on dilepton polarization in heavy-ion collisions

TL;DR

This paper investigates how weak magnetic fields in high-energy heavy-ion collisions influence dilepton polarization, revealing that dilepton angular distributions are sensitive probes of the magnetic field's orientation and strength.

Contribution

It introduces a formalism incorporating weak magnetic effects into dilepton production, highlighting their impact on polarization and angular distribution in quark-gluon plasma.

Findings

Anisotropic coefficients in dilepton spectra are sensitive to magnetic field orientation.

Dilepton angular distributions serve as effective probes for weak magnetic fields.

Weak magnetic effects significantly influence dilepton polarization patterns.

Abstract

The measurement of the magnetic field created in high-energy heavy-ion collisions is challenging, due the the fact that the magnetic field decays so drastically that in a thermalized quark-gluon plasma the field strength becomes rather weak. By incorporating the weak magnetic effect into the medium, and especially into the production formalism of dileptons from the quark-gluon plasma, the effect of dilepton polarization is studied through the dilepton angular distribution. We find that the anisotropic coefficients in the dilepton spectrum are quite sensitive to the orientation and strength of the weak field. Accordingly, these coefficients provide ideal probes for the magnetic field in realistic experiments.