# Multiplicity Dependence of Non-extensive Parameters for Strange and Multi-Strange Particles in Proton-Proton Collisions at $\sqrt{s}= 7$ TeV at the LHC

## TL;DR

This study analyzes the transverse momentum spectra of strange particles in proton-proton collisions at 7 TeV using Tsallis distribution, revealing mass ordering and multiplicity dependence of freeze-out parameters, indicating system equilibration trends.

## Contribution

It provides the first detailed analysis of non-extensive parameters and freeze-out conditions for multiple strange particles as functions of multiplicity and mass in high-energy pp collisions.

## Key findings

- Non-extensive parameter q decreases with multiplicity.
- Strange particle temperature increases with multiplicity.
- Freeze-out volume shows mass ordering and weak multiplicity dependence.

## Abstract

The transverse momentum ($p_{\rm T}$) spectra in proton-proton collisions at $\sqrt{s}$ = 7 TeV, measured by the ALICE experiment at the LHC are analyzed with a thermodynamically consistent Tsallis distribution. The information about the freeze-out surface in terms of freeze-out volume, temperature and the non-extenisivity parameter, $q$, for $K^{0}_{S}$, $\Lambda+\bar{\Lambda}$, $\Xi^{-}+\bar{\Xi}^{+}$ and $\Omega^{-}+\bar{\Omega}^{+}$ are extracted by fitting the $p_{\rm T}$ spectra with Tsallis distribution function. The freeze-out parameters of these particles are studied as a function of charged particle multiplicity density ($dN_{ch}/d\eta$). In addition, we also study these parameters as a function of particle mass to see any possible mass ordering. The strange and multi-strange particles show mass ordering in volume, temperature, non-extensive parameter and also a strong dependence on multiplicity classes. It is observed that with increase in particle multiplicity, the non-extensivity parameter, $q$ decreases, which indicates the tendency of the produced system towards thermodynamic equilibration. The increase in strange particle multiplicity is observed to be due to the increase of temperature and not to the size of the freeze-out volume.