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arXiv · 2608.28000

Hyperon bulk viscosity effects in neutron-star inspirals

Elena M. Kantor·Mikhail E. Gusakov·Kirill Y. Kraav
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Abstract

The paper revisits the role of hyperon bulk viscosity during neutron-star inspiral. We find that hyperon bulk viscosity exerts only a minor influence on the gravitational-wave phase, causing a phase shift of $\sim 10^{-3}\,\rm rad$. This shift is too small to be detected by existing gravitational-wave observatories, and it seems unlikely that next-generation detectors will be able to isolate this effect from other factors. However, our analysis indicates that hyperon bulk viscosity can significantly heat the hyperon core of a neutron star, raising its temperature to approximately $5 \times 10^8\,\rm K$.

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Elena M. Kantor, Mikhail E. Gusakov, Kirill Y. Kraav. 2026-08-28. Hyperon bulk viscosity effects in neutron-star inspirals. https://arxiv.org/abs/2608.28000

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