Role of chemical potential at kinetic freeze-out using Tsallis non-extensive statistics in proton-proton collisions at the Large Hadron Collider

Abstract

The charged-particle transverse momentum spectra (pT-spectra) measured by the ALICE collaboration for pp collisions at s= 7 and 13 TeV have been studied using a thermodynamically consistent form of Tsallis non-extensive statistics. The Tsallis distribution function is fitted to the pT-spectra and the results are analyzed as a function of final state charged-particle multiplicity for various light flavor and strange particles, such as π±,K±,p+p¯,ϕ,Λ+Λ¯,Ξ+Ξ¯,Ω+Ω¯. At the LHC energies, particles and antiparticles are produced in equal numbers. However, the equality of particle and antiparticle yields at the kinetic freeze-out may imply that they have the same but opposite chemical potential which is not necessarily zero. We use an alternative procedure that makes use of parameter redundancy, by introducing a finite chemical potential at the kinetic freeze-out stage. This article emphasizes the importance of the chemical potential of the system produced in pp collisions at the LHC energies using the Tsallis distribution function which brings the system to a single freeze-out scenario. © The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2024.