An analytic hydrodynamical model of rotating 3D expansion in heavy-ion collisions

TL;DR

This paper introduces an exact analytic hydrodynamical model for rotating, expanding 3D fireballs in heavy-ion collisions, providing formulas to analyze rotation effects and infer properties of quark-gluon plasma.

Contribution

It presents a novel exact solution for rotating 3D expansion in non-relativistic hydrodynamics, enabling direct analysis of rotation effects in heavy-ion collision observables.

Findings

Analytic formulas for azimuthal oscillations of Bose-Einstein correlations.

Method to determine fireball rotation from flow measurements.

Potential to infer quark-gluon plasma equation of state.

Abstract

A new exact and analytic solution of non-relativistic fireball hydrodynamics is presented. It describes an expanding triaxial ellipsoid that rotates around one of its principal axes. The observables are calculated using simple analytic formulas. Azimuthal oscillation of the off-diagonal Bertsch-Pratt radii of Bose-Einstein correlations as well as rapidity dependent directed and third flow measurements provide means to determine the magnitude of the rotation of the fireball. Observing this rotation and its dependence on collision energy may lead to new information on the equation of state of the strongly interacting quark gluon plasma produced in high energy heavy ion collisions.