Dynamics of particle production in Pb--Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV using PYTHIA8 Angantyr model

TL;DR

This paper investigates particle production in Pb--Pb collisions at 2.76 TeV using PYTHIA8 Angantyr, highlighting the roles of multi-parton interactions and color reconnection in reproducing experimental data and mimicking collective effects.

Contribution

It demonstrates that PYTHIA8 Angantyr with proper tuning can effectively model key observables in heavy-ion collisions, including multiplicity, transverse momentum, and particle yield ratios.

Findings

PYTHIA8 Angantyr reproduces charged-particle multiplicity and mean pT distributions.

Color reconnection and MPI mimic signs of collectivity in heavy-ion collisions.

Predictions for pT spectra and yield ratios align with experimental observations.

Abstract

We study the dynamics of identified, strange, and multi-strange particle production in Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV using the recently developed Angantyr model, incorporated within PYTHIA8. We show the interplay between multi-parton interactions (MPI) and color reconnection (CR) on the experimentally measured quantities. The charged-particle multiplicity ($N_{\rm ch}$) and mean transverse momentum ($\langle p_{\rm T}\rangle$) distributions are well explained by PYTHIA8 Angantyr with proper tuning, as presented in this paper. Predictions of $p_{\rm T}$ spectra, $\langle p_{\rm T} \rangle$, $p_{\rm T}$ integrated yields of the identified, strange and multi-strange particles are studied. To provide insight into the collective nature of the produced particles, we look into the ratio of particle yields to pions and kaons. PYTHIA8 Angantyr with CR and MPI mimic signs of collectivity and is possibly one of the suitable candidates to study ultra-relativistic heavy-ion collisions.