Transverse momentum decorrelation of the flow vector in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV

TL;DR

This study uses the AMPT model to analyze transverse momentum-dependent flow fluctuations in Pb-Pb collisions at 5.02 TeV, providing insights into initial conditions and the quark-gluon plasma's properties.

Contribution

It offers a systematic investigation of flow fluctuations with the AMPT model, highlighting the influence of initial state fluctuations and improving constraints on initial conditions.

Findings

AMPT reasonably describes flow fluctuations observed in data.

Flow fluctuations are primarily driven by initial state fluctuations.

Model comparisons help constrain initial conditions of heavy-ion collisions.

Abstract

The individual studies of the anisotropic flow vector, flow angle and flow magnitude fluctuations with multi-particle correlations provide insight into the initial conditions and properties of the quark-gluon plasma (QGP) created in high-energy heavy-ion collisions. Recent measurements of these fluctuations have been available and the comparison to hydrodynamic models shows unique sensitivities to the initial conditions of the system, but also a puzzling dependence on the specific shear viscosity $\eta/s$. In this paper, a systematic study with A Multi-Phase Transport (AMPT) model using different tunings of the initial conditions, partonic cross section and hadronic interactions investigates the $p_{\rm T}$-dependent flow vector, flow angle and flow magnitude fluctuations. It is found that the transport model reasonably describes the flow vector, flow angle and flow magnitude fluctuations observed in data and that the fluctuations are driven by fluctuations in the initial state. The comparison of data and model presented in this paper enables further constraints on the initial conditions of the heavy-ion collisions.