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arXiv · 2410.14778

Disappearance of a massive star in the Andromeda Galaxy due to formation of a black hole

Kishalay De·Morgan MacLeod·Jacob E. Jencson·Elizabeth Lovegrove·Andrea Antoni·Erin Kara·Mansi M. Kasliwal·Ryan M. Lau·Abraham Loeb·Megan Masterson·Aaron M. Meisner·Christos Panagiotou·Eliot Quataert·Robert Simcoe
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Abstract

When a massive star reaches the end of its lifetime, its core collapses and releases neutrinos that drive a shock into the outer layers (stellar envelope). A sufficiently strong shock ejects the envelope, producing a supernova. If the shock fails to eject it, the envelope is predicted to fall back onto the collapsing core, producing a stellar-mass black hole (BH) and causing the star to disappear. We report observations of M31-2014-DS1, a hydrogen-depleted supergiant in the Andromeda Galaxy. In 2014 it brightened in the mid-infrared. From 2017 to 2022 it faded by factors of $\gtrsim10^4$ in optical light, becoming undetectable, and $\gtrsim10$ in total light. We interpret these observations, and those of a previous event in NGC 6946, as evidence for failed supernovae forming stellar-mass BHs.

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Kishalay De, Morgan MacLeod, Jacob E. Jencson, Elizabeth Lovegrove, Andrea Antoni, Erin Kara, Mansi M. Kasliwal, Ryan M. Lau, Abraham Loeb, Megan Masterson, Aaron M. Meisner, Christos Panagiotou, Eliot Quataert, Robert Simcoe. 2024-10-18. Disappearance of a massive star in the Andromeda Galaxy due to formation of a black hole. https://doi.org/10.1126/science.adt4853

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