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arXiv · hep-ph/0004045

Enhanced antiproton production in Pb(160 AGeV)+Pb reactions: evidence for quark gluon matter?

M. Bleicher·M. Belkacem·S. A. Bass·S. Soff·H. Stöcker
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Abstract

The centrality dependence of the antiproton per participant ratio is studied in Pb(160 AGeV)+Pb reactions. Antiproton production in collisions of heavy nuclei at the CERN/SPS seems considerably enhanced as compared to conventional hadronic physics, given by the antiproton production rates in $pp$ and antiproton annihilation in $\bar{p}p$ reactions. This enhancement is consistent with the observation of strong in-medium effects in other hadronic observables and may be an indication of partial restoration of chiral symmetry.

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M. Bleicher, M. Belkacem, S. A. Bass, S. Soff, H. Stöcker. 2000-04-06. Enhanced antiproton production in Pb(160 AGeV)+Pb reactions: evidence for quark gluon matter?. https://doi.org/10.1016/s0370-2693(00)00643-2

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