Kinetic freeze-out spectra of identified particles produced in p–Pb collisions at $\sqrt {s_{NN} }$ = 5.02 TeV

Abstract

We study the transverse momentum spectra of identified pions (π^– + π⁺), kaons ((K ^– + K ⁺), K ^s₀ ), protons (p + p̅) and lambda hyperons (Λ + Λ̅) produced at mid-rapidity (0 < y _cm < 0.5) in most central (0‒5)% p–Pb collisions at $\sqrt {s_{NN} }$ = 5.02 TeV in comparison with a Unified Statistical Thermal Freeze-out Model (USTFM). The measurements for pions are reported upto p _T = 3 GeV, the kaons (K ^– + K ⁺) are reported upto p _T = 2.5 GeV, K ^s₀ is reported upto p _T = 7 GeV, and the baryons (protons and lambda hyperons) are reported upto p _T = 3.5 GeV. A good agreement is seen between the calculated results and the experimental data points taken from the ALICE experiment. The transverse momentum spectra are found to be flatter for heavy particles than for light particles. Bulk freeze-out properties in terms of kinetic freeze-out temperature and the transverse collective flow velocity are extracted from the fits of the transverse momentum spectra of these hadrons. The effect of resonance decay contributions has also been taken care of.