Analysis of particle production in ultrarelativistic heavy-ion collisions within a two-source statistical model

Abstract

The experimental data on hadron yields and ratios in central lead-lead and gold-gold collisions at 158 AGeV/c (SPS) and √ s = 130 AGeV (RHIC), respectively, are analysed within a two-source statistical model of an ideal hadron gas. A comparison with the standard thermal model is given. The two sources, which can reach the chemical and thermal equilibrium separately and may have different temperatures, particle and strangeness densities, and other thermodynamic characteristics, represent the expanding system of colliding heavy ions, where the hot central fireball is embedded in a larger but cooler fireball. The volume of the central source increases with rising bombarding energy. Results of the two-source model fit to RHIC experimental data at midrapidity coincide with the results of the one-source thermal model fit, indicating the formation of an extended fireball, which is three times larger than the corresponding core at SPS.

Hot and dense hadronic matter in an effective mean-field approach

“…Concerning the hadronic phase, hadron resonance gas models have turned out to be very successful in describing particle abundances produced in (ultra)relativistic heavy-ion collisions [17][18][19]. In this framework, to take phenomenologically into account the interaction between hadrons at finite densities, finite size corrections have been considered in the excluded volume approximation [20][21][22][23][24][25].…”

Strangeness production in heavy ion collisions at SPS and RHIC within two-source statistical model

“…The proposed two-source statistical model (TSM) of a hadron gas [16] divides the whole reaction zone into two regions: the outer region (source 1 or S1) and the inner region (source 2 or S2). The two sources are allowed to possess different temperatures, net baryon and strangeness densities, etc.…”