Speaker
Torsten Dahms
(TUM)
Description
The goal of ultra-relativistic heavy-ion collisions at the LHC is to study the properties of the quark-gluon plasma (QGP), a phase of matter with partonic degrees of freedom. Electromagnetic radiation, in form of photons or lepton pairs, is a penetrating probe that allows the investigation of the full time evolution and dynamics of the produced matter, as it does not undergo strong interaction in the final state. The dilepton spectrum is extremely rich in physics sources: Thermal black-body radiation is of particular interest as it carries information about the QGP temperature. Modification of the spectral function of light vector mesons are linked to the potential restoration of chiral symmetry in the QGP phase. Correlated lepton pairs from semi-leptonic charm and beauty decays provide additional information about the heavy-quark energy loss. Furthermore, the suppression pattern of quarkonium states with different binding energies in a QGP gives access to an independent temperature measurement. In this talk, results on quarkonium suppression and low-mass dilepton measurements at RHIC and the LHC will be reviewed. Finally, an outlook for low-mass dilepton measurements with the ALICE experiment at the LHC will be given.
