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Direct Photon Production in 158 AGeV Pb+Pb Collisions

T. Peitzmann
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Abstract

A measurement of direct photon production in Pb+Pb collisions at 158 AGeV has been carried out in the CERN WA98 experiment. The invariant yield of direct photons in central collisions is extracted as a function of transverse momentum in the interval 0.5 < pT < 4 GeV/c. A significant direct photon signal, compared to statistical and systematical errors, is seen at pT > 1.5 GeV/c. The results constitute the first observation of direct photons in ultrarelativistic heavy-ion collisions which could be significant for diagnosis of quark gluon plasma formation.

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T. Peitzmann. 2000-09-18. Direct Photon Production in 158 AGeV Pb+Pb Collisions. https://doi.org/10.1016/s0375-9474(01)00556-5

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