Phenomenological analysis of rapidity distribution of negative pions in central ¹²C+¹²C collisions at $\sqrt{s_{nn}} = 3.14\, {\rm GeV}$

Abstract

Various aspects of the simple phenomenological model, the grand combinational model (GCM), proposed earlier for the systematic description of the center-of-mass (cm) rapidity distributions of different particles produced in high energy heavy ion collisions, were analyzed. The values of GCM parameters were extracted from fitting the cm rapidity distributions of the negative pions in 12 C+ 12 C collisions at √ snn = 3.14 GeV both in the experiment and using Modified FRITIOF Model. The GCM parameters extracted for the central 12 C+ 12 C collisions were compared with those obtained in central Pb+Pb collisions at super proton synchrotron (SPS) and alternating gradient synchrotron (AGS) energies between √ snn = 6.3 GeV and √ snn = 12.3 GeV and in central Au+Au collisions at Relativistic heavy ion collider (RHIC) energies between √ snn = 19.6 GeV and √ snn = 200 GeV. The plausible physical interpretations for the GCM parameters were given. The initial assumption that the parameter β of GCM should be zero for symmetric systems with identical colliding nuclei was validated. The parameter γ of GCM was deduced to follow an approximate asymptotic behavior (γ → 0 as √ snn → ∞) at very large cm energies, and γ ∼ = 0 could possibly be related to complete dehadronization of the whole collision system, along with attaining its maximum possible energy density, in central collisions of identical nuclei. The behavior of cm energy § Corresponding author. 1550049-1 Int. J. Mod. Phys. E 2015.24. Downloaded from www.worldscientific.com by UNIVERSITY OF IOWA on 09/11/16. For personal use only. Kh. K. Olimov et al.dependence of γ suggested that it could possibly be sensitive to deconfinement phase transition.

Excitation functions of parameters extracted from three-source (net-)proton rapidity distributions in Au-Au and Pb-Pb collisions over an energy range from AGS to RHIC

“…Rapidity (or pseudorapidity) distributions of charged particles produced in nucleusnucleus (heavy ion) collisions at high energies are an important topic measured in experiments and analyzed in theories [1][2][3]. In particular, the rapidity distributions of protons and net-protons (protons minus antiprotons, i.e.…”