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Topological susceptibility at zero and finite temperature in the Nambu-Jona-Lasinio model

K. Ohnishi·K. Fukushima·K. Ohta
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Abstract

We consider the three flavor Nambu-Jona-Lasinio model with the 't Hooft interaction incorporating the U(1)_A anomaly. In order to set the coupling strength of the 't Hooft term, we employ the topological susceptibility $χ$ instead of the eta' meson mass. The value for $χ$ is taken from lattice simulations. We also calculate $χ$ at finite temperature within the model. Comparing it with the lattice data, we extract information about the behavior of the U(1)_A anomaly at finite temperature. We conclude that within the present framework, the effective restoration of the U(1)_A symmetry does not necessarily take place even at high temperature where the chiral symmetry is restored.

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K. Ohnishi, K. Fukushima, K. Ohta. 2001-03-06. Topological susceptibility at zero and finite temperature in the Nambu-Jona-Lasinio model. https://doi.org/10.1103/physrevc.63.045203

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