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arXiv · 2110.07164

AT2018lqh: Black Hole Born from a Rotating Star?

Daichi Tsuna·Kazumi Kashiyama·Toshikazu Shigeyama
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Abstract

Recently an intriguing transient AT 2018lqh, with only a day-scale duration and a high luminosity of $7\times 10^{42}\ {\rm erg\ s^{-1}}$, has been discovered. While several possibilities are raised on its origin, the nature of this transient is yet to be unveiled. We propose that a black hole (BH) with $\sim 30\, M_\odot$ forming from a rotating blue supergiant can generate a transient like AT 2018lqh. We find that this scenario can consistently explain the optical/UV emission and the tentative late-time X-ray detection, as well as the radio upper limits. If super-Eddington accretion onto the nascent BH powers the X-ray emission, continued X-ray observations may be able to test the presence of an accretion disk around the BH.

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Daichi Tsuna, Kazumi Kashiyama, Toshikazu Shigeyama. 2021-10-14. AT2018lqh: Black Hole Born from a Rotating Star?. https://doi.org/10.3847/2041-8213%2Fac3997

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