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arXiv · 2108.03324

Beta equilibrium under neutron star merger conditions

Mark G. Alford·Alexander Haber·Steven P. Harris·Ziyuan Zhang
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Abstract

We calculate the nonzero-temperature correction to the beta equilibrium condition in nuclear matter under neutron star merger conditions, in the temperature range $1\,$MeV$ < T \lesssim 5\,$MeV. We improve on previous work by using a consistent description of nuclear matter based on the IUF and SFHo relativistic mean field models. This includes using relativistic dispersion relations for the nucleons, which we show is essential in these models. We find that the nonzero-temperature correction can be of order $10$ to $20\,$MeV, and plays an important role in the correct calculation of Urca rates, which can be wrong by factors of $10$ or more if it is neglected.

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Mark G. Alford, Alexander Haber, Steven P. Harris, Ziyuan Zhang. 2021-08-06. Beta equilibrium under neutron star merger conditions. https://doi.org/10.3390/universe7110399

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