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arXiv · 1911.04878

Energy density at kinetic freeze-out in Pb-Pb collisions at the LHC using the Tsallis distribution

M. D. Azmi·T. Bhattacharyya·J. Cleymans·M. Paradza
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Abstract

The thermodynamic parameters like energy density, pressure, entropy density, temperature and particle density are determined from the transverse momentum distributions of charged particles in Pb-Pb collisions at the LHC. The results show a clear increase with the centrality and the beam energy in all parameters. It is determined that in the final freeze-out stage the energy density reaches a value of about 0.039 GeV/fm$^3$ for the most central collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. This is less than that at chemical freeze-out where the energy density is about 0.36 GeV/fm$^3$. This decrease approximately follows a $T^4$ law. The results for the pressure and entropy density are also presented for each centrality class at $\sqrt{s_{NN}}$ = 2.76 and 5.02 TeV.

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M. D. Azmi, T. Bhattacharyya, J. Cleymans, M. Paradza. 2020-01-18. Energy density at kinetic freeze-out in Pb-Pb collisions at the LHC using the Tsallis distribution. https://doi.org/10.1088/1361-6471%2Fab6c33

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