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arXiv · 1805.08713

Axial anomaly and hadronic properties in a nuclear medium

G. Fejos·A. Hosaka
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Abstract

We investigate meson and nucleon dynamics at finite baryon density and temperature by coupling the nucleon field and the omega meson to the three-flavor linear sigma model and calculate hadronic properties around the nuclear liquid-gas transition. We apply the functional renormalization group method, and find that mesonic fluctuations increase the strength of the coefficient of the $U_A(1)$ breaking determinant operator as a function of the chiral condensate. As a consequence, we find that the actual value of the anomaly increases discontinuously at the first order nuclear liquid-gas transition. We calculate how mesonic masses and partial restoration of chiral symmetry are modified due to such an effect.

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G. Fejos, A. Hosaka. 2018-08-21. Axial anomaly and hadronic properties in a nuclear medium. https://doi.org/10.1103/physrevd.98.036009

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