Anti-Proton Evolution in Little Bangs and Big Bang
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.
Keywords
Cite
@article{arxiv.0705.2003,
title = {Anti-Proton Evolution in Little Bangs and Big Bang},
author = {H. Schade and B. Kampfer},
journal= {arXiv preprint arXiv:0705.2003},
year = {2009}
}