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arXiv · 0705.2003

Anti-Proton Evolution in Little Bangs and Big Bang

H. Schade·B. Kampfer
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Abstract

The abundances of anti-protons and protons are considered within momentum-integrated Boltzmann equations describing Little Bangs, i.e., fireballs created in relativistic heavy-ion collisions. Despite of a large anti-proton annihilation cross section we find a small drop of the ratio of anti-protons to protons from 170 MeV (chemical freeze-out temperature) till 100 MeV (kinetic freeze-out temperature) for CERN-SPS and BNL-RHIC energies thus corroborating the solution of the previously exposed "ani-proton puzzle". In contrast, the Big Bang evolves so slowly that the anti-baryons are kept for a long time in equilibrium resulting in an exceedingly small fraction. The adiabatic path of cosmic matter in the phase diagram of strongly interacting matter is mapped out.

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H. Schade, B. Kampfer. 2009-03-30. Anti-Proton Evolution in Little Bangs and Big Bang. https://doi.org/10.1103/physrevc.79.044909

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