Statistical hadronization model analysis of hadron yields in p + Nb and Ar + KCl at SIS18 energies

The HADES data from p + Nb collisions at a center-of-mass energy of √sNN = 3.2 GeV are analyzed employing a statistical hadronization model. The model can successfully describe the production yields of the identified hadrons π0, η, Ʌ, K0 s, ω with parameters Tchem = (99 ± 11) MeV and μb = (619 ± 34) MeV, which fit well into the chemical freeze-out systematics found in heavy-ion collisions. In addition, we reanalyze our previous HADES data from Ar + KCl collisions at √SNN = 2.6 GeV with an updated version of the model. We address equilibration in heavy-ion collisions by testing two aspects: the description of yields and the regularity of freeze-out parameters from a statistical model fit as a function of colliding energy and system size. Despite its success, the model fails to describe the observed Ξ- yields in both, p + Nb and Ar + KCl. Special emphasis is put on feed-down contributions from higher-lying resonance states as a possible explanation for the observed excess. © 2016, SIF, Springer-Verlag Berlin Heidelberg. 52 6 Cited By :6