Darmstadt 2016 – wissenschaftliches Programm
HK 62.2: Hauptvortrag
Freitag, 18. März 2016, 11:15–11:45, S1/01 A1
Electromagnetic Probes of the Quark-Gluon Plasma — •Torsten Dahms — Excellence Cluster Universe, TUM, Garching, Germany
Electromagnetic probes, i. e. lepton pairs or photons, provide an excellent probe of the Quark-Gluon Plasma (QGP) produced in nuclear collisions at ultrarelativistic energies. Lepton pairs and photons are emitted, e. g. as blackbody radiation, during all stages of the collision. They preserve information about the properties of the medium at the time of emission as they remain unperturbed by strong final state interactions. Thus, their momentum and, in case of lepton pairs, their invariant-mass distributions are sensitive to the medium temperature but also to modifications caused by a possible restoration of chiral symmetry that is spontaneously broken in vacuum and responsible for the generation of hadron masses. Measurements of such signals are extremely challenging due to the large background from ordinary hadron decays.
This talk will review the latest developments at the Relativistic Heavy Ion Collider and the Large Hadron Collider in the quest to measure the temperature of the QGP and to understand whether and how chiral symmetry is restored.