Event topology and constituent-quark scaling of elliptic flow in heavy-ion collisions at the Large Hadron Collider using a multiphase transport model

TL;DR

This study uses the AMPT model to analyze how event shape, characterized by transverse spherocity, influences elliptic flow and quark scaling in heavy-ion collisions at the LHC, revealing shape-dependent effects on particle flow and hadronization.

Contribution

It introduces the use of transverse spherocity to investigate elliptic flow and constituent-quark scaling, highlighting shape-dependent phenomena in heavy-ion collision dynamics.

Findings

Elliptic flow varies with transverse spherocity and centrality.

NCQ-scaling is violated in jetty-like events with low spherocity.

Fragmentation dominates hadronization in high-momentum jetty events.

Abstract

Transverse spherocity is an event shape observable, which separates the events based on their geometrical shapes. In this work, we use transverse spherocity to study the identified light flavor production in heavy-ion collisions using A Multi-Phase Transport (AMPT) model. We obtain the elliptic flow coefficients for pions, kaons and protons in Pb+Pb collisions at $\sqrt{s_{\rm{NN}}} = 5.02$ TeV as a function of transverse spherocity and collision centrality. Also, we study the number of constituent-quark (NCQ) scaling of elliptic flow which interprets the dominance of the quark degrees of freedom at the early stages of the collision. We observe a clear dependence of the elliptic flow for identified particles on transverse spherocity. It is found that the NCQ-scaling is strongly violated in events with low transverse spherocity compared to transverse spherocity-integrated events, confirming the fragmentation-based hadronization mechanism for high-momentum partons involved in the dynamics of jetty-like events.