e+e- Pairs: a clock and a thermometer of heavy ion collisions
arXiv:0805.0153 · doi:10.1088/0954-3899/35/10/104037
Abstract
Recently, there is growing evidence that a new state of matter is formed in sqrt(s_NN)= 200 GeV Au+Au collisions at RHIC: a strongly coupled Quark Gluon Plasma of partonic degrees of freedom which develops a collective motion. Dilepton spectra are not affected by strong interaction and can therefore probe the whole time evolution of the collision. Thus they may be sensitive to onset of deconfinement, chiral symmetry restoration, as well as the production of thermal photons. The PHENIX experiment measured the production of e+e- pairs in p+p and Au+Au collisions at sqrt(s_NN)= 200 GeV. An enhanced dilepton yield in the mass range 150<m_ee<750 MeV/c^2 is measured. The excess increases faster with centrality than the number of participating nucleons and is concentrated at p_T<1GeV/c. At higher p_T the excess below 300 MeV/c^2 has been related to an enhanced production of direct photons possibly of thermal origin.
Proceedings of Quark Matter 2008, 8 pages, 7 figures
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Cited by in corpus (11)
- Hadron properties in the nuclear medium
- Hadrons in strongly interacting matter
- Analysis of dilepton production in Au+Au collisions at sqrt(s_NN)=200 GeV within the Parton-Hadron-String Dynamics (PHSD) transport approach
- Phenomenology of photon and di-lepton production in relativistic nuclear collisions
- Radial Flow from Electromagnetic Probes and Signal of Quark Gluon Plasma
- Dilepton production in the strongly interacting quark-gluon plasma
- Measuring radial flow of partonic and hadronic phases in relativistic heavy ion collision
- Dilepton production from parton interactions in the early stage of relativistic heavy-ion collisions
- Di-electron Continuum at PHENIX
- Dileptons from the nonequilibrium Quark-Gluon Plasma
- Summary of Experimental Results: Photons, Leptons and Heavy Quarks