Hydrodynamic fluctuations and two-point correlations

TL;DR

This paper investigates how initial state fluctuations in energy density, modeled as localized hotspots, evolve hydrodynamically and influence two-point correlations in azimuthal angle and rapidity, shedding light on experimental data from RHIC and LHC.

Contribution

It introduces a detailed hydrodynamic model of localized initial fluctuations and analyzes their impact on two-point energy density correlations in heavy-ion collisions.

Findings

Localized fluctuations produce characteristic correlation patterns.

Hydrodynamic evolution affects the azimuthal and rapidity dependence of correlations.

Results may help interpret experimental two-particle correlation data.

Abstract

We examine correlations of energy density induced by initial state fluctuations, which are localized in both transverse and longitudinal extent. The hotspots are evolved according to hydrodynamics in a background which includes radial flow. Two-point energy density correlations from these hotspots are computed as a function of the difference in azimuthal angle and rapidity. Such localized perturbations occur naturally in the theory of hydrodynamic fluctuations and may provide insight into some features of the two-particle correlation data from RHIC and the LHC.