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arXiv · 2302.02989

Nuclear and Hybrid Equations of State in Light of the Low-Mass Compact Star in HESS J1731-347

Liam Brodie·Alexander Haber
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Abstract

We sample over $500$ relativistic mean-field theories constrained by chiral effective field theory and properties of isospin-symmetric nuclear matter and test them against known stellar structure constraints. This includes a recent mass and radius measurement of a compact object in supernova remnant HESS J1731-347, with an unusually low mass of $M=0.77^{+0.20}_{-0.17}\,M_{\odot}$ and a compact radius of $R=10.4^{+0.86}_{-0.78}$ km. We show that none of the sampled nuclear models meet all constraints at the $68\,\%$ credibility level, but that hybrid equations of state with a quark matter inner core and nuclear outer core easily can. This indicates a tension between astrophysical constraints and low-energy nuclear theory.

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Liam Brodie, Alexander Haber. 2023-02-06. Nuclear and Hybrid Equations of State in Light of the Low-Mass Compact Star in HESS J1731-347. https://doi.org/10.1103/physrevc.108.025806

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