Charge-dependent transverse momentum and its impact on the search for the chiral magnetic wave

TL;DR

This paper investigates how charge-dependent transverse momentum correlations, arising from local charge conservation, can affect the search for the chiral magnetic wave in heavy-ion collisions.

Contribution

It reveals the origin of the charge asymmetry and transverse momentum correlation using string fragmentation models, highlighting a potential background in CMW searches.

Findings

Charge asymmetry correlates with transverse momentum due to local charge conservation.

The $A_{ch}-p_T$ correlation varies with different kinematic conditions.

Insights into collective motion of quark-gluon plasma are provided.

Abstract

The chiral magnetic wave (CMW) is sought using the charge asymmetry ($A_{\rm ch}$) dependence of anisotropic flow in heavy-ion collisions. The charge dependent transverse momentum ($p_{\rm T}$), however, could play a role as a background. With the string fragmentation models, including PYTHIA, we demonstrate the origin of the $A_{\rm ch}-p_{\rm T}$ correlation and its connection with the local charge conservation (LCC). The impact of $A_{\rm ch}-p_{\rm T}$ and its behavior in varied kinematic windows are also discussed. This study provides more insights for the search for the CMW and comprehending the collective motion of the quark-gluon plasma.