Can GW231123 have a stellar origin?

ABSTRACT The gravitational wave event GW231123 detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) interferometers during their fourth observing run features two black holes (BHs) with source-frame masses of $137^{+23}_{-18}$ and $101^{+22}_{-50}\,{\rm M}_\odot$ – in the range of the pair-instability BH mass gap predicted by standard stellar evolution theory. Both BHs are also inferred to be rapidly spinning ($\chi _1 \simeq 0.9$, $\chi _2 \simeq 0.8$). The primary object in GW231123 is the heaviest stellar mass BH detected to date, which, together with its extreme rotation, raises questions about its astrophysical origin. Accounting for the unusually large spin of ${\sim} 0.9$ with…

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  Multiple Sclerosis Center of Atlanta

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  University of Hawai'i
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  Fondazione Cariplo

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  Materials Research Institute, Pennsylvania State University

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  Science and Technology Facilities Council

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  H2020 Marie Skłodowska-Curie Actions

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