Examination of the observability of a chiral magnetically-driven charge-separation difference in collisions of the $\mathrm{^{96}_{44}Ru +\, ^{96}_{44}Ru}$ and $\mathrm{^{96}_{40}Zr +\, ^{96}_{40}Zr}$ isobars at energies available at RHIC

TL;DR

This study uses AVFD model calculations and charge-sensitive correlators to investigate the charge separation difference from the Chiral Magnetic Effect in Ru+Ru and Zr+Zr collisions at RHIC, finding a measurable 10% CME-driven difference.

Contribution

The paper demonstrates the potential to detect and characterize CME-induced charge separation differences in isobaric collisions using advanced modeling and correlator techniques.

Findings

Larger charge separation in Ru+Ru than Zr+Zr collisions.

Approximately 10% CME-driven charge separation difference.

Strategy to evaluate background influence on charge separation measurements.

Abstract

Anomalous Viscous Fluid Dynamics (AVFD) model calculations for $\mathrm{^{96}_{44}Ru +\, ^{96}_{44}Ru}$ and $\mathrm{^{96}_{40}Zr +\, ^{96}_{40}Zr}$ collisions ($\sqrt{s_{\rm NN}} = 200$ GeV) are used in concert with a charge-sensitive correlator, to test its ability to detect and characterize the charge separation difference expected from the Chiral Magnetic Effect (CME) in these isobaric collisions. The tests indicate a larger charge separation for $\mathrm{^{96}_{44}Ru +\, ^{96}_{44}Ru}$ than for $\mathrm{^{96}_{40}Zr +\, ^{96}_{40}Zr}$ collisions, and a discernible CME-driven difference of $\sim 10$\% in the presence of realistic non-CME backgrounds. They also indicate a strategy for evaluating the relative influence of the background correlations, present for each isobar. These results suggest that charge separation measurements for these isobaric species could serve to further constrain unambiguous identification and characterization of the CME in upcoming measurements at RHIC.