Analyzing the Correlation Between Thermal and Kinematic Parameters in Various Multiplicity Classes within 7 and 13 TeV pp Collisions

TL;DR

This study analyzes how thermal and kinematic parameters in proton-proton collisions at 7 and 13 TeV relate to multiplicity, using the blast wave model with Tsallis statistics, revealing parameter dependencies and correlations.

Contribution

It introduces a detailed analysis of parameter dependencies and correlations in pp collisions at different energies and multiplicities within the TBW framework, including flow correction effects.

Findings

Flow velocity drops to zero after a certain multiplicity class.

Parameters like temperature and q increase slightly with energy but decrease with multiplicity.

Correlations between parameters and multiplicity are identified and characterized.

Abstract

We investigate the transverse momentum spectra of identified particles at 7 TeV and 13 TeV in pp collisions in the framework of the blast wave model with Tsallis statistics (TBW). Based on experimental data by ALICE Collaboration, we observe that the model describes the $p_T$ spectra well with the common Tsallis temperature (T) and flow velocity (\beta_T) but separate non-extensive parameters (q) for baryons and mesons. The parameter dependence on multiplicity as well as on collision energy is investigated, and a strong dependence on the former while a weak dependence on the latter is reported. The extracted parameters in this work consist of the initial temperature (T_i), the average transverse momentum (<p_T>), the T, \beta_T, and the q. These parameters are found to increase a little with increasing energy, however, they (except the parameter q) decrease significantly with decreasing multiplicity. We observe that $\beta_T$ drops to zero after the multiplicity class VII, while, $T$ and $q$ do not change their behavior. Furthermore, our analysis explore the correlations among different parameters, including associations with the charged particle multiplicity per unit pseudorapidity (dN_{ch}/d\eta). The correlation between T and beta_T, T and dN_{ch}/d\eta, \beta_T and dN_{ch}/d\eta, T_i and <p_T> and T_i and dN_{ch}/d\eta demonstrates a positive relationship, while, the correlation between T and q-1, and q-1 and dN_{ch}/d\eta is negative. Finally, we implement an extra flow correction on the T parameter. Our findings reveal that the Doppler-corrected temperature parameter aligns closely with the T in scenarios with lower multiplicities. However, as the multiplicity increases, a noticeable divergence emerges between these parameters, indicating a widening separation between them.