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Heavy neutron star phenomenology with an H dibaryon

Jesper Leong*, Pierre A. M. Guichon, and Anthony W. Thomas

  • CSSM and ARC Centre of Excellence for Dark Matter Particle Physics, Department of Physics, Adelaide University, 5005 Adelaide, SA, Australia

  • *Contact author: jesper.leong@adelaide.edu.au
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Phys. Rev. C 113, 015809 – Published 28 January, 2026

DOI: https://doi.org/10.1103/qs6f-1css

Abstract

The equation of state for dense nuclear matter in β equilibrium is explored including the possibility of a doubly strange H particle. Consistent with experimental constraints, the mass of the H in free space is taken to be near the ΛΛ threshold. Within the quark-meson coupling model, which we use, no new parameters are required to describe the interaction between the H dibaryon and the other baryons. Compared with the case where only octet baryons are included, the maximum mass is only slightly reduced and the tidal deformability is essentially unchanged with this addition. In heavy neutron stars the H is abundant and extends nearly 6 km from the center of the star.

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Outline

Information

Phys. Rev. C 113, 015809– Published 28 January, 2026
  • Received 8 April 2025
  • Revised 29 September 2025
  • Accepted 24 November 2025
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