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arXiv · 2311.05689

Measuring the nuclear equation of state with neutron star-black hole mergers

Nikhil Sarin·Hiranya V. Peiris·Daniel J. Mortlock·Justin Alsing·Samaya M. Nissanke·Stephen M. Feeney
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Abstract

Gravitational-wave (GW) observations of neutron star-black hole (NSBH) mergers are sensitive to the nuclear equation of state (EOS). We present a new methodology for EOS inference with non-parametric Gaussian process (GP) priors, enabling direct constraints on the pressure at specific densities and the length-scale of correlations on the EOS. Using realistic simulations of NSBH mergers, incorporating both GW and electromagnetic (EM) selection to ensure sample purity, we find that a GW detector network operating at O5-sensitivities will constrain the radius of a $\unit[1.4]{M_{\odot}}$ NS and the maximum NS mass with $1.6\%$ and $13\%$ precision, respectively. With the same sample, the projected constraint on the length-scale of correlations in the EOS is $\geq~\unit[3.2]{MeV~fm^{-3}}$. These results demonstrate strong potential for insights into the nuclear EOS from NSBH systems, provided they are robustly identified.

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Nikhil Sarin, Hiranya V. Peiris, Daniel J. Mortlock, Justin Alsing, Samaya M. Nissanke, Stephen M. Feeney. 2023-11-09. Measuring the nuclear equation of state with neutron star-black hole mergers. https://arxiv.org/abs/2311.05689

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