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arXiv · 1706.09701

The $d^*(2380)$ in neutron stars - a new degree of freedom?

I. Vidaña·M. Bashkanov·D. P. Watts·A. Pastore
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Abstract

Elucidating the appropriate microscopic degrees of freedom within neutron stars remains an open question which impacts nuclear physics, particle physics and astrophysics. The recent discovery of the first non-trivial dibaryon, the $d^*(2380)$, provides a new candidate for an exotic degree of freedom in the nuclear equation of state at high matter densities. In this paper a first calculation of the role of the $d^*(2380)$ in neutron stars is performed, based on a relativistic mean field description of the nucleonic degrees of freedom supplemented by a free boson gas of $d^*(2380)$. The calculations indicate that the $d^*(2380)$ would appear at densities around three times normal nuclear matter saturation density, influencing the upper mass limit for a stable neutron star and the neutron and proton fractions. New possibilities for neutron star cooling mechanisms arising from the $d^*(2380)$ are also predicted.

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I. Vidaña, M. Bashkanov, D. P. Watts, A. Pastore. 2017-06-28. The $d^*(2380)$ in neutron stars - a new degree of freedom?. https://doi.org/10.1016/j.physletb.2018.03.052

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