Centrality, transverse momentum and collision energy dependence of the Tsallis parameters in relativistic heavy-ion collisions
Bogolyubov Institute for Theoretical Physics, National Academy of Sciences of Ukraine, Kiev, Ukraine
2 CERN, CH 1211, Geneva, Switzerland
3 University of Jammu, 180006, Jammu, India
4 National Institute of Science Education and Research, 752050, Jatni, India
Accepted: 9 June 2021
Published online: 29 June 2021
The thermodynamic properties of matter created in high-energy heavy-ion collisions have been studied in the framework of the non-extensive Tsallis statistics. The transverse momentum () spectra of identified charged particles (pions, kaons, protons) and all charged particles from the available experimental data of Au-Au collisions at the Relativistic Heavy Ion Collider (RHIC) energies and Pb-Pb collisions at the Large Hadron Collider (LHC) energies are fitted by the Tsallis distribution. The fit parameters, q and T, measure the degree of deviation from an equilibrium state and the effective temperature of the thermalized system, respectively. The spectra are well described by the Tsallis distribution function from peripheral to central collisions for the wide range of collision energies, from = 7.7 GeV to 5.02 TeV. The extracted Tsallis parameters are found to be dependent on the particle species, collision energy, centrality, and fitting ranges in . For central collisions, both q and T depend strongly on the fit ranges in . For most of the collision energies, q remains almost constant as a function of centrality, whereas T increases from peripheral to central collisions. For a given centrality, q systematically increases as a function of collision energy, whereas T has a decreasing trend. A profile plot of q and T with respect to collision energy and centrality shows an anti-correlation between the two parameters.
© The Author(s) 2021
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