Axial inverse magnetic catalysis

TL;DR

This paper demonstrates the emergence of inverse magnetic catalysis for axial symmetry in QCD around the chiral crossover, using a NJL model with anomalous magnetic moments, and suggests it can be tested on lattice simulations.

Contribution

It introduces the concept of axial inverse magnetic catalysis in QCD and shows it can be modeled with a NJL framework including anomalous magnetic moments.

Findings

AIMC occurs near the chiral crossover in thermomagnetic QCD.

Anomalous magnetic moments are crucial for AIMC and CIMC.

The results are testable on lattice simulations.

Abstract

We find that the inverse magnetic catalysis for $U(1)$ axial symmetry (AIMC: axial inverse magnetic catalysis) can emerge around the chiral crossover regime in the thermomagnetic QCD with 2 + 1 flavors at physical point. This phenomenon can be correlated with the IMC for the chiral $SU(2)_L \times SU(2)_R$ symmetry (CIMC: chiral IMC). We explicitly observe the AIMC based on a Nambu-Jona-Lasinio model with 2 + 1 quark flavors, where introduced anomalous magnetic moments of the quarks play the essential role to drive both the CIMC and AIMC. Our finding is shortly testable on lattices. Possible phenomenological and cosmological implications are also briefly addressed.