On the Charge Separation Effect in Relativistic Heavy Ion Collisions

TL;DR

This paper proposes a new method using the charged dipole vector to measure charge separation and local parity violation in relativistic heavy ion collisions, demonstrating its effectiveness with Monte Carlo simulations.

Contribution

It introduces a novel event-by-event charge separation measurement technique that can distinguish true effects from background correlations.

Findings

Method successfully detects charge separation in simulated data

Can differentiate between genuine charge separation and two-particle correlation effects

Potential to improve understanding of local parity violation in heavy ion collisions

Abstract

In this paper, we discuss alternative means of measuring the possible presence of local parity violation in relativistic heavy ion collisions. We focus on the phenomenon of charge separation and introduce the charged dipole vector $\hat{Q}^c_1$, which will measure the charge separation on an event-by-event basis. Using Monte Carlo events, we demonstrate the method and its discriminating power. In particular we show that such an analysis will reveal the strength of charge separation effect and its azimuthal correlation with the reaction plane. We further show that our proposed method may be able to distinguish between the actual charge separation effect and effects due to certain two particle correlations. The connection to present measurements based on particle correlations is discussed.