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arXiv · 1908.03023

Kinetic freeze-out in central heavy-ion collisions between 7.7 and 2760 GeV per nucleon pair

Ivan Melo·Boris Tomasik
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Abstract

We fit the single-particle $p_t$ spectra of identified pions, kaons, and (anti)protons from central collisions of gold or lead nuclei at energies between 7.7 and 2760~GeV per nucleon pair. Blast wave model with included resonance production and with an assumption of partial chemical equilibrium is used and the fits are performed with the help of a Gaussian emulator process. A kinetic freeze-out temperature is found about 100~MeV for the lowest collision energies and 80~MeV at the LHC. The average transverse expansion velocity grows with increasing $\sqrt{s_{NN}}$ from 0.45 to 0.65. Due to partial chemical equilibrium, the influence of resonance decays on the shape of the $p_t$ spectra for $\sqrt{s_{NN}}$ above 27~GeV is small.

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Ivan Melo, Boris Tomasik. 2019-10-26. Kinetic freeze-out in central heavy-ion collisions between 7.7 and 2760 GeV per nucleon pair. https://doi.org/10.1088/1361-6471%2Fab5f03

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