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Ratios of charged antiparticles to particles near mid-rapidity in Au+Au collisions at sqrt(s_NN) = 130 GeV

B. B. Back
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Abstract

We have measured the ratios of antiparticles to particles for charged pions, kaons and protons near mid-rapidity in central Au+Au collisions at sqrt(s_NN) = 130 GeV. For protons, we observe pbar/p = 0.60 +/- 0.04 (stat.) +/- 0.06 (syst.) in the transverse momentum range 0.15 < p_T < 1.0 GeV/c. This leads to an estimate of the baryo-chemical potential mu_B of 45 MeV, a factor of 5-6 smaller than in central Pb+Pb collisions at sqrt(s_NN) = 17.2 GeV.

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B. B. Back. 2001-04-18. Ratios of charged antiparticles to particles near mid-rapidity in Au+Au collisions at sqrt(s_NN) = 130 GeV. https://doi.org/10.1103/physrevlett.87.102301

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