Statistical description with anisotropic momentum distributions for hadron production in nucleus nucleus collisions
Abstract
Various experimental data at AGS, SPS and RHIC energies on hadron particle yields for central heavy ion collisions are investigated by employing a generalized statistical density operator that allows for a welldefined anisotropic local momentum distribution for each particle species, specified by a common streaming velocity parameter. The individual particle ratios are rather insensitive to a change in this new intensive parameter. This leads to the conclusion that the reproduction of particle ratios by a statistical treatment does not imply the existence of a fully isotropic local momentum distribution at hadrochemical freezeout, i.e. a state of almost complete thermal equilibrium.
 Publication:

Journal of Physics G Nuclear Physics
 Pub Date:
 May 2004
 DOI:
 10.1088/09543899/30/5/004
 arXiv:
 arXiv:nuclth/0305008
 Bibcode:
 2004JPhG...30..597S
 Keywords:

 heavy ion collisionshadron productionstatistical model;
 Nuclear Theory;
 High Energy Physics  Phenomenology
 EPrint:
 14 pages, revtex, 3 figures accepted version, to be published in Journal of Physics G