# Dileptons from the strongly-interacting Quark-Gluon Plasma within the Parton-Hadron-String-Dynamics (PHSD) approach

## TL;DR

This paper investigates dilepton production in heavy-ion collisions using the PHSD transport approach, revealing the roles of vector meson broadening and off-shell quark-antiquark annihilation in the quark-gluon plasma.

## Contribution

It introduces a detailed microscopic model that reproduces experimental dilepton spectra, highlighting the importance of nonperturbative QGP effects.

## Key findings

- Low mass dilepton spectra match data with vector meson broadening.
- Intermediate mass spectra are dominated by off-shell quark-antiquark annihilation.
- Reproduces the softening of the mT spectra at intermediate masses.

## Abstract

Dilepton production in In+In collisions at 158 AGeV is studied within the microscopic Parton-Hadron-Strings Dynamics (PHSD) transport approach, which is based on a dynamical quasiparticle model (DQPM) matched to reproduce lattice QCD results in thermodynamic equilibrium. A comparison to the data of the NA60 Collaboration shows that the low mass dilepton spectra are well described by including a collisional broadening of vector mesons, while the spectra in the intermediate mass range are dominated by off-shell quark-antiquark annihilation in the nonperturbative QGP. In particular, the observed softening of the mT spectra at intermediate masses is reproduced.