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Renormalization-group invariant mean-field analysis of the parity-doublet model for nuclear and neutron-star matter

Mattia Recchi1,*, Lorenz von Smekal1,2, and Jochen Wambach3,4

  • *Contact author: mattia.recchi@theo.physik.uni-giessen.de
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Phys. Rev. D 114, 014032 – Published 17 July, 2026

DOI: https://doi.org/10.1103/ysr2-s9cs

Abstract

The parity-doublet model (PDM) is a chirally invariant effective theory for strong-interaction matter involving nucleons and their opposite-parity partners in a parity-doubling framework. We introduce a multiplicatively renormalizable mean-field approach to include the baryonic vacuum contributions to the resulting grand-canonical potential in an explicitly renormalization-group invariant form. As an application, we evaluate the pertinent thermodynamics of two-flavor symmetric and asymmetric nuclear matter, focusing on the restoration of spontaneously broken chiral symmetry at baryon densities and temperatures relevant for the astrophysics of neutron stars. Special attention is paid to the effect of the baryonic vacuum fluctuations on the evolution of the chiral condensate with baryon density and temperature for specific choices of the chirally invariant baryon mass m0 to demonstrate the importance of consistently including these vacuum fluctuations in the PDM.

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Phys. Rev. D 114, 014032– Published 17 July, 2026
  • Received 15 December 2025
  • Accepted 18 June 2026
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