Effect of charged particle's multiplicity fluctuations on flow harmonics in even-by-event hydrodynamics

TL;DR

This paper investigates how fluctuations in charged particle multiplicity affect flow harmonics in nucleus-nucleus collisions using event-by-event hydrodynamics, finding minimal impact from these fluctuations.

Contribution

The study introduces a generalized Monte-Carlo Glauber model incorporating multiplicity fluctuations governed by a negative binomial distribution.

Findings

Multiplicity fluctuations have little effect on flow harmonics.

The generalized model accurately simulates initial conditions.

Flow harmonic results are robust against multiplicity fluctuations.

Abstract

In nucleon-nucleon collisions, charged particle's multiplicity fluctuates. We have studied the effect of multiplicity fluctuation on flow harmonics in nucleus-nucleus collision in event-by-event hydrodynamics. Assuming that the charged particle's multiplicity fluctuations are governed by the negative binomial distribution, the Monte-Carlo Glauber model of initial condition is generalised to include the fluctuations. Explicit simulations with the generalised Monte-Carlo Glauber model initial conditions indicate that the multiplicity fluctuations do not have large effect on the flow harmonics.