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arXiv · 2503.21167

Heavy Neutron Star Phenomenology with an H-dibaryon

Jesper Leong·Anthony W. Thomas·Pierre A. M. Guichon
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Abstract

The equation of state for dense nuclear matter in $\beta$-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 $\Lambda \, \Lambda$ 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. 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 as far as 6 km from the center of the core.

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Jesper Leong, Anthony W. Thomas, Pierre A. M. Guichon. 2025-03-27. Heavy Neutron Star Phenomenology with an H-dibaryon. https://doi.org/10.1103/qs6f-1css

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