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arXiv · 1801.01682

Nambu--Jona-Lasinio model in a parallel electromagnetic field

Lingxiao Wang·Gaoqing Cao·Xu-Guang Huang·Pengfei Zhuang
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Abstract

We explore the features of the $U_A(1)$ and chiral symmetry breaking of the Nambu--Jona-Lasinio model without the Kobayashi-Maskawa-'t Hooft determinant term in the presence of a parallel electromagnetic field. We show that the electromagnetic chiral anomaly can induce both finite neutral pion condensate and isospin-singlet pseudo-scalar $\eta$ condensate and thus modifies the chiral symmetry breaking pattern. In order to characterize the strength of the $U_A(1)$ symmetry breaking, we evaluate the susceptibility associated with the $U_A(1)$ charge. The result shows that the susceptibility contributed from the chiral anomaly is consistent with the behavior of the corresponding $\eta$ condensate. The spectra of the mesonic excitations are also studied.

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Lingxiao Wang, Gaoqing Cao, Xu-Guang Huang, Pengfei Zhuang. 2018-01-05. Nambu--Jona-Lasinio model in a parallel electromagnetic field. https://doi.org/10.1016/j.physletb.2018.03.018

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