Thermal photons and dileptons
نویسنده
چکیده
The study of penetrating probes constitutes a key aspect of the relativistic heavy ion program. In the hadronic sector, jet quenching, for example, has been a striking revelation, and has contributed to expose the qualitatively different physics that appeared in the transition from the SPS to RHIC. In this context, electromagnetic radiation also defines a privileged class of observables owing mainly to the absence of final state interactions. We briefly review some recent developments in the measurement of lowand intermediatemass lepton pairs, and then address real photon measurements at RHIC, together with the observed supression in the hard parton spectrum.
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