Extraction of freezeout parameters and their dependence on collision energy and collision cross-section

TL;DR

This study employs the Blast wave model with Boltzmann Gibbs statistics to analyze transverse momentum spectra from various collision experiments, extracting freezeout parameters and examining their dependence on collision energy and system size.

Contribution

It introduces a comprehensive analysis of freezeout parameters across different collision energies and sizes using a specific statistical model, providing new insights into collision dynamics.

Findings

Kinetic freezeout temperature increases with collision energy and system size.

Transverse flow remains unchanged with energy but varies with system size.

Freeze-out volume and mean transverse momentum increase with energy and system size.

Abstract

We used the Blast wave model with Boltzmann Gibbs statistics and analyzed the experimental data of transverse momentum spectra ($p_T$) measured by NA61/SHINE and NA 49 Collaborations in inelastic (INEL) proton-proton, and the most central Beryllium-Beryllium (Be-Be), Argon-Scandium (Ar-Sc) and Lead-Lead (Pb-Pb) collisions. The model results fit the experimental data of NA61/SHINE and NA 49 Collaborations very well. We extracted kinetic freezeout temperature, transverse flow velocity and kinetic freezeout volume directly from the spectra. We also calculated mean transverse momentum and initial temperature from the fit function. It is observed that the kinetic freezeout temperature increases with increasing the collision energy as well as collision cross-section (size of the colliding system). Furthermore, the transverse flow remains unchanged with increasing the collision energy, while it changes randomly with the collision cross-section. Similarly, with the increase in collision energy or the collision cross-section, the freeze-out volume and the average $p_T$ increase. The initial temperature is also observed to be an increasing function of the collision cross-section.