Exact strangeness conservation in heavy ion collisions

Krzysztof Redlich,Natasha Sharma

doi:10.1051/epjconf/202225907002

Abstract

We investigate the increase in strangeness production with charged particle multiplicity (dNch/dy) seen by the ALICE collaboration at CERN in p-p, p-Pb and Pb-Pb collisions using the hadron resonance gas model. The strangeness canonical ensemble is used taking into account the interactions among hadrons using S-matrix corrections based on known phase shift analyses. We show the essential role of constraints due to the exact conservation of strangeness which is instrumental to describing observed features of strange particle yields and their scaling with dNch/dy. Furthermore, the results on comparing the hadron resonance gas model with and without S-matrix corrections, are presented. We observe that the interactions introduced by the phase shift analysis via the S-matrix formalism are essential for a better description of the yields data independent of collision system. This work is based on our longlasting collaboration and most recent publications with Jean Cleymans.

Highlights

The experimental particle yeild data from heavy-ion collisions across different experiments and broad range of energies have been shown to originate from a thermal production [1,2,3,4,5,6,7]
It has been shown that the freezeout temperature obtained from the hadron gas model (HRG) conincides with the chiral crossover temperature from lattice QCD (LQCD) at vanishingly small finite μB [8]
We have studied the effect of global strangeness quantum number conservation on strangeness production in heavy-ion and elementary collisions in a given acceptance region using the hadron resonance gas (HRG) model in the canonical ensemble

Summary

Introduction

The experimental particle yeild data from heavy-ion collisions across different experiments and broad range of energies have been shown to originate from a thermal production [1,2,3,4,5,6,7]. These data have been successfully explained by the hadron gas model (HRG) with a common freezeout temperature T f and chemical potentials μ f associated with the conserved charges.

Strangeness production and HRG model

S-matrix formalism and HRG

Comparison of results with ALICE data

Summary