Thermodynamic and transport properties in Au + Au collisions at RHIC energies from the clustering of color strings

TL;DR

This paper analyzes thermodynamic and transport properties in Au+Au collisions at RHIC energies by extracting initial temperature and related quantities from experimental data, comparing results with lattice QCD, and exploring the deconfinement transition.

Contribution

It introduces a method to determine initial thermodynamic properties from RHIC data and compares these with lattice QCD, providing insights into the deconfinement transition energy range.

Findings

Initial temperature and energy density are extracted from experimental spectra.

Deconfinement transition likely occurs between 11.5 and 19.6 GeV.

Results are consistent with lattice QCD calculations.

Abstract

In this work, we have extracted the initial tempearture from the transverse momentum spectra of charged particles in $Au+Au$ collisions using STAR data at RHIC energies from $\sqrt{s_{NN}}$ = 7.7 to 200 GeV. The initial energy density ($\varepsilon$), shear viscosity to entropy density ratio ($\eta/s$), trace anomaly ($\Delta$), the squared speed of sound ($C_s^2$), entropy density, and bulk viscosity to entropy density ratio ($\zeta/s$) are obtained and compared with the lattice QCD calculations for (2+1) flavor. The initial temperatures obtained are compared with various hadronization and chemical freeze-out temperatures. The analysis of the data shows that the deconfinement to confinement transition possibly takes place between $\sqrt{s_{NN}}$ = 11.5 and 19.6 GeV.