We analyze the transverse momentum spectra of charged pions measured in Au+Au collisions at sNN = 200 GeV and in Pb+Pb collisions at sNN = 2.76 TeV using the Tsallis distribution modified to include transverse flow. All the spectra are well described by the modified Tsallis distribution in an extended transverse momentum range upto 6 GeV/c. The kinetic freeze-out temperature (T), average transverse flow (β) and degree of non thermalization (q) are obtained as a function of system size for both the energies. With increasing system size β shows increasing trend whereas T remains constant. While the systems at RHIC and LHC energies show similar β and q, the parameter T is higher at LHC as compared to RHIC. The kinetic freeze-out temperature is also extracted using the measured charged particle multiplicity and HBT volume of the system as a function of system size and collision energies.
@article{arxiv.1505.05258,
title = {Inferring freeze-out parameters from pion measurements at RHIC and LHC},
author = {Priyanka Sett and Prashant Shukla},
journal= {arXiv preprint arXiv:1505.05258},
year = {2015}
}