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arXiv · nucl-ex/0305036

Scaling properties of proton and anti-proton production in sqrt(s_NN) = 200 GeV Au + Au collisions

Abstract

We report on the yield of protons and anti-protons, as a function of centrality and transverse momentum, in Au+Au collisions at sqrt(s_NN) = 200 GeV measured at mid-rapidity by the PHENIX experiment at RHIC. In central collisions at intermediate transverse momenta (1.5 < p_T < 4.5 GeV/c) a significant fraction of all produced particles are protons and anti-protons. They show a centrality-scaling behavior different from that of pions. The p-bar/pion and p/pion ratios are enhanced compared to peripheral Au+Au, p+p, and electron+positron collisions. This enhancement is limited to p_T < 5 GeV/c as deduced from the ratio of charged hadrons to pi^0 measured in the range 1.5 < p_T < 9 GeV/c.

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PHENIX Collaboration, S. S. Adler. 2003-08-29. Scaling properties of proton and anti-proton production in sqrt(s_NN) = 200 GeV Au + Au collisions. https://doi.org/10.1103/physrevlett.91.172301

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