Anisotropic flow fluctuations in hydro-inspired freeze-out model for relativistic heavy ion collisions

TL;DR

This paper analyzes LHC PbPb collision data on harmonic flow fluctuations using the HYDJET++ model, demonstrating that flow fluctuations originate dynamically and can be reproduced by introducing spatial anisotropy distributions.

Contribution

It shows that a simple modification of the hydro-inspired model with spatial anisotropy distributions can accurately reproduce flow fluctuation data from LHC collisions.

Findings

HYDJET++ model reproduces elliptic and triangular flow fluctuations

Flow fluctuations have a dynamical origin in the model

Model matches experimental eccentricity fluctuations

Abstract

The LHC data on event-by-event harmonic flow coefficients measured in PbPb collisions at center-of-mass energy 2.76 TeV per nucleon pair are analyzed and interpreted within the HYDJET++ model. To compare the model results with the experimental data the unfolding procedure is employed. The essentially dynamical origin of the flow fluctuations in hydro-inspired freeze-out approach has been established. It is shown that the simple modification of the model via introducing the distribution over spatial anisotropy parameters permits HYDJET++ to reproduce both elliptic and triangular flow fluctuations and related to it eccentricity fluctuations of the initial state at the LHC energy.