Exploring UA(1) symmetry restoration in a magnetic field by meson screening masses in the NJL model
Abstract
We investigate the effective axial UA(1) symmetry restoration at finite temperature in an external magnetic field using meson screening masses, as well as meson susceptibilities, in a (2+1)-flavor Nambu-Jona-Lasinio (NJL) model. To incorporate inverse magnetic catalysis, we employ a magnetic-field-dependent four-quark coupling constrained by the lattice QCD chiral pseudo-critical temperature, with the 't Hooft coupling fixed. In the lattice-improved NJL model, the longitudinal screening mass difference between the UA(1) partners δ0 and π0 and their normalized meson susceptibility difference exhibit axial magnetic catalysis at low temperatures and axial inverse magnetic catalysis near the chiral crossover, whereas the transverse screening mass difference increases with eB at all temperatures. Despite these different responses, the axial pseudo-critical temperatures extracted from the thermal inflection points of these three alternative order parameters decrease with eB, implying that a decreasing pseudo-critical temperature can coexist with an increasing transverse screening mass difference at fixed temperature.
Related
- Dual symmetry breaking and magnetic charge screening
- NJL-Chiral Soliton and the Nucleon Equation of State at supra-saturation density: Impact of Chiral Symmetry Restoration
- Evidence of Taste-Symmetry restoration for Kähler-Dirac fermions on Euclidean Dynamical Triangulations
- Quantum Mpemba effect of Z2 symmetry restoration in the Dicke model
- Level-Four Modular Symmetry Selected by the Harmonic Pattern of Quark and Lepton Masses
BibTeX
@misc{sheng2026exploring,
title = {{Exploring $U_A(1)$ symmetry restoration in a magnetic field by meson screening masses in the NJL model}},
author = {Bing-Kai Sheng and Zigeng Ding and Danning Li and Xinyang Wang and Lang Yu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.35468},
eprint = {2609.35468},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.35468},
}
RIS
TY - UNPB
TI - Exploring U_A(1) symmetry restoration in a magnetic field by meson screening masses in the NJL model
AU - Bing-Kai Sheng
AU - Zigeng Ding
AU - Danning Li
AU - Xinyang Wang
AU - Lang Yu
PY - 2026
DA - 2026/09/28
PB - arXiv
DO - 10.48550/arxiv.2609.35468
UR - https://arxiv.org/abs/2609.35468
AB - We investigate the effective axial U_A(1) symmetry restoration at finite temperature in an external magnetic field using meson screening masses, as well as meson susceptibilities, in a (2+1)-flavor Nambu-Jona-Lasinio (NJL) model. To incorporate inverse magnetic catalysis, we employ a magnetic-field-dependent four-quark coupling constrained by the lattice QCD chiral pseudo-critical temperature, with the 't Hooft coupling fixed. In the lattice-improved NJL model, the longitudinal screening mass difference between the U_A(1) partners δ^0 and π^0 and their normalized meson susceptibility difference exhibit axial magnetic catalysis at low temperatures and axial inverse magnetic catalysis near the chiral crossover, whereas the transverse screening mass difference increases with eB at all temperatures. Despite these different responses, the axial pseudo-critical temperatures extracted from the thermal inflection points of these three alternative order parameters decrease with eB, implying that a decreasing pseudo-critical temperature can coexist with an increasing transverse screening mass difference at fixed temperature.
ER -