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arXiv · hep-ph/9404325

Where the excess photons and dileptons in SPS nuclear collisions come from?

E. V. Shuryak·L. Xiong
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Abstract

Recently the first single photon spectra from CERN energy heavy-ion collisions were reported by WA80, while NA34/3 and NA38 have obtained the spectra for dileptons with the mass up to 4-5 GeV. The production rates for photons and dileptons significantly increase when reactions involving the $A_1$ meson are included. However, with the conventional expansion scenario, the absolute yields are still significantly smaller than the observed ones. It may indicate that expansion in the ``mixed state" takes much more time.

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E. V. Shuryak, L. Xiong. 1994-04-22. Where the excess photons and dileptons in SPS nuclear collisions come from?. https://doi.org/10.1016/0370-2693(94)90148-1

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