Probes of the Quark–gluon Plasma as it might be Produced in Ultra-relativistic Nuclear Collisions

摘要

The energy densities which might be achieved in ultrarelativistic nuclear collisions are discussed. Using these estimates, promising probes of a quark–gluon plasma as it might be produced in such collisions are reviewed. I discuss in detail the emission of photons and di-leptons. The consequences of hydrodynamic expansion and a first order phase transition are explored for the transverse momentum spectrum of hadrons. Fluctuations in the rapidity distribution of hadrons are also discussed as a possible signal for a first order phase transition. The possibility that copious production of strange particles may signal the production of a quark–gluon plasma is critically assessed.