Temperature and fluid velocity on the freeze-out surface from $π$, $K$, $p$ spectra in pp, p-Pb and Pb-Pb collisions

Abstract

We present a new approach to take into account resonance decays in the blast-wave model fits of identified hadron spectra. Thanks to pre-calculated decayed particle spectra, we are able to extract, in a matter of seconds, the multiplicity dependence of the single freeze-out temperature Tfo , average fluid velocity ⟨βT⟩, velocity exponent n, and the volume dV/dy of an expanding fireball. In contrast to blast-wave fits without resonance feed-down, our approach results in a freeze-out temperature of Tfo∼155MeV, which has only weak dependence on multiplicity and collision system. Finally, we discuss the case of separate chemical and kinetic freeze-outs.