Study of Dependence of Kinetic Freezeout Temperature on the Production Cross Section of Particles in Various Centrality Intervals in Au Au and Pb Pb Collisions at High Energies

TL;DR

This study analyzes how the kinetic freezeout temperature depends on particle production cross sections across different centralities in high-energy nucleus-nucleus collisions, revealing a double freezeout scenario and variations with collision centrality.

Contribution

It introduces a detailed analysis of kinetic freezeout parameters for multiple particles, highlighting separate freezeout conditions for strange and non-strange particles in heavy-ion collisions.

Findings

Non-strange and strange particles freeze out separately.

Freezeout volume and flow velocity decrease with particle mass.

Central collisions have larger freezeout temperature and volume.

Abstract

Transverse momentum spectra of pion, proton, lambda, cascade, Omega and deuteron (d) in different centrality intervals in nucleus nucleus collisions at the center of mass energy are analyzed by the blast wave model with Boltzmann Gibbs statistics. We extracted the kinetic freezeout temperature, transverse flow velocity and kinetic freezeout volume from the transverse momentum spectra of the particles. It is observed that the non-strange and strange (multi strange) particles freezeout separately due to different reaction cross-sections. While the freezeout volume and transverse flow velocity are mass dependent, they decrease with the resting mass of the particles. The present work reveals the scenario of a double kinetic freezeout in nucleus nucleus collisions. Furthermore, the kinetic freezeout temperature and freezeout volume are larger in central collisions than peripheral collisions. However, the transverse flow velocity remains almost unchanged from central to peripheral collisions.