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arXiv · 2009.10908

On the Speed of Sound in Hyperonic Stars

T. F. Motta·P. A. M. Guichon·A. W. Thomas
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Abstract

We build upon the remarkable, model independent constraints on the equation of state of dense baryonic matter established recently by Annala et al. [1]. Using the quark-meson coupling model, an approach to nuclear structure based upon the self-consistent adjustment of hadron structure to the local meson fields, we show that, once hyperons are allowed to appear in dense matter in \b{eta}-equilibrium, the equation of state is consistent with those constraints. As a result, while one cannot rule out the occurence of quark matter in the cores of massive neutron stars, the available constraints are also compatible with the presence of hyperons.

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T. F. Motta, P. A. M. Guichon, A. W. Thomas. 2021-02-16. On the Speed of Sound in Hyperonic Stars. https://doi.org/10.1016/j.nuclphysa.2021.122157

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