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

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.Comment: talk given at the 21st International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter 2009), to be published in Nucl.Phys.A, 4 pages, 3 figures, elsarticle styl