Speaker
Description
The study of event-by-event mean transverse momentum ($\langle p_{\rm T} \rangle$) fluctuations is reported in terms of the integral two-particle correlator ($\langle \Delta p_{\rm T} \Delta p_{\rm T}\rangle$) and skewness of the event-wise $\langle p_{\rm T} \rangle$ distribution in proton$-$proton (pp) collisions at $\sqrt{s}=13$ TeV. The simulations were carried out using the Monte Carlo event generators PYTHIA8 and HERWIG7. Charged particles with transverse momentum ($p_{\rm T}$) and pseudo-rapidity ($\eta$) ranges $0.15 \leq p_{\rm T}\leq 2.0$ GeV/$c$ and $|\eta| \leq 0.8$ were taken into the consideration. The correlator $\langle \Delta p_{\rm T} \Delta p_{\rm T}\rangle$ is observed to follow distinct declining trends with the average charged particle multiplicity ($\langle N_{\rm ch} \rangle$) for PYTHIA8 and HERWIG7 models. Furthermore, both models yield positive finite skewness in low-multiplicity events. The observables are additionally studied using the transverse spherocity estimator ($S_{\rm 0}$) to comprehend the relative contributions of hard scattering (jets) and soft multi-partonic interactions (MPI) to the observed fluctuations. The comparative measurements using these models would help in understanding the fluctuation dynamics and constraint the particle productions in such models.
