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arXiv · 2109.14759

GW200115: a non-spinning black hole -- neutron star merger

Ilya Mandel·Rory J. E. Smith
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Abstract

GW200115 was the second merger of a black hole and a neutron star confidently detected through gravitational waves. Inference on the signal allows for a large black hole spin misaligned with the orbital angular momentum, but shows little support for aligned spin values. We show that this is a natural consequence of measuring the parameters of a black hole -- neutron star binary with non-spinning components while assuming the priors used in the LIGO-Virgo-KAGRA analysis. We suggest that, a priori, a non-spinning binary is more consistent with current astrophysical understanding.

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Ilya Mandel, Rory J. E. Smith. 2021-09-29. GW200115: a non-spinning black hole -- neutron star merger. https://doi.org/10.3847/2041-8213%2Fac35dd

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