From Wigner distributions of photons to dilepton production in semicentral heavy ion collisions

TL;DR

This paper introduces a new formalism for calculating dilepton production in semicentral heavy ion collisions using the polarization density matrix from Wigner distributions, enabling detailed distribution analysis and comparison with experimental data.

Contribution

The paper develops a novel approach that incorporates the full photon polarization density matrix for more accurate dilepton distribution calculations in heavy ion collisions.

Findings

Good agreement with experimental data for invariant mass distributions

Detailed analysis of impact parameter contributions

New insights into dilepton transverse momentum and acoplanarity distributions

Abstract

We present a formalism how to calculate differential distributions for dilepton production in semicentral heavy ion collisions. In this new approach, the differential cross section is calculated using the complete polarization density matrix of photons resulting from the Wigner distribution formalism. The formalism is used to calculate different distributions of the invariant mass, dilepton transverse momentum and acoplanarity for different regions of centrality. The results of the calculation are compared with recent experimental data. We also study the contribution from different parts of impact parameter space.