Quantification of Chiral Magnetic Effect from Event-by-Event Anomalous-Viscous Fluid Mechanics

TL;DR

This paper introduces an advanced simulation framework, AVFD, that models the Chiral Magnetic Effect in heavy ion collisions, providing quantitative predictions and background estimates to aid experimental interpretation.

Contribution

The paper presents a new event-by-event anomalous viscous fluid dynamics model that integrates CME signal prediction with background effects in heavy ion collisions.

Findings

Quantitative CME signal predictions for isobaric collisions.

Assessment of background contributions in CME measurements.

Framework validated against existing experimental data.

Abstract

Chiral Magnetic Effect (CME) is the macroscopic manifestation of the fundamental chiral anomaly in a many-body system of chiral fermions, and emerges as anomalous transport current in hydrodynamic framework. Experimental observation of CME is of great interest and significant efforts have been made to look for its signals in heavy ion collisions. Encouraging evidence of CME-induced charge separation has been reported from both RHIC and LHC, albeit with ambiguity due to potential background contributions. Crucial for addressing such issue, is the need of quantitative predictions for both CME signal and the non-CME background consistently, with sophisticated modeling tool. In this contribution we report a recently developed Anomalous Viscous Fluid Dynamics (AVFD) framework, which simulates the evolution of fermion currents in QGP on top of the data-validated VISHNU bulk hydro evolution. In particular, this framework has been extended to event-by-event simulations with proper implementation of known flow-driven background contributions. We report quantitative results from such simulations and evaluate the implications for interpretations of current experimental measurements. Finally we give our prediction for the CME signal in upcoming isobaric collisions.