Charge-dependent correlations in heavy-ion collisions from stochastic hydrodynamics

Abstract

Charge-dependent correlations from both background and charge separation contribute to experimental observables in heavy-ion collisions. In this paper, we use stochastic hydrodynamics to study background charge asymmetry due to fluctuations. Using the rapidity-dependent correlation and a simple ansatz for particle distributions, we find a fluctuation-induced correlation to provide a type of background F-correlation. Experimental data for Au+Au collisions at are compared. We also make predictions for F-correlations in isobar collisions. Combining this with our previous chiral magnetic effect results, we obtain δ-correlations for collisions in the three types of system. Computations from our model show an almost identical background with less than 2% difference for isobars, but roughly 10% difference for their charge separations. In combination with our earlier works, we provide a consistent method of calculating both the chiral magnetic effect and the charged background in the context of stochastic hydrodynamics.