Flow harmonics within an analytically solvable viscous hydrodynamic model

TL;DR

This paper presents an analytical viscous hydrodynamic model to compute flow harmonics in heavy-ion collisions, revealing how viscous effects and system parameters influence harmonic scaling and mixing.

Contribution

It introduces an analytically solvable viscous hydrodynamic model with anisotropic perturbations to study flow harmonic behavior in heavy-ion collisions.

Findings

Shear viscous corrections grow linearly with harmonic number n.

Flow harmonics scale with system size, viscosity, and collision energy.

Harmonic mixing effects are analyzed within the model.

Abstract

Based on a viscous hydrodynamic model with anisotropically perturbed Gubser flow and isothermal Cooper-Frye freezeout at early times, we analytically compute the flow harmonics $v_n(p_T)$ and study how they scale with the harmonic number $n$ and transverse momentum, as well as the system size, shear and bulk viscosity coefficients, and collision energy. In particular, we find that the magnitude of shear viscous corrections grows linearly with $n$. The mixing between different harmonics is also discussed. While this model is rather simple as compared to realistic heavy-ion collisions, we argue that the scaling results presented here may be meaningfully compared to experimental data collected over many energies, system sizes, and geometries.