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arXiv · 2311.10195

Minutes-duration Optical Flares with Supernova Luminosities

Abstract

In recent years, certain luminous extragalactic optical transients have been observed to last only a few days. Their short observed duration implies a different powering mechanism from the most common luminous extragalactic transients (supernovae) whose timescale is weeks. Some short-duration transients, most notably AT2018cow, display blue optical colours and bright radio and X-ray emission. Several AT2018cow-like transients have shown hints of a long-lived embedded energy source, such as X-ray variability, prolonged ultraviolet emission, a tentative X-ray quasiperiodic oscillation, and large energies coupled to fast (but subrelativistic) radio-emitting ejecta. Here we report observations of minutes-duration optical flares in the aftermath of an AT2018cow-like transient, AT2022tsd (the "Tasmanian Devil"). The flares occur over a period of months, are highly energetic, and are likely nonthermal, implying that they arise from a near-relativistic outflow or jet. Our observations confirm that in some AT2018cow-like transients the embedded energy source is a compact object, either a magnetar or an accreting black hole.

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Anna Y. Q. Ho, Daniel A. Perley, Ping Chen, Steve Schulze, Vik Dhillon, Harsh Kumar, Aswin Suresh, Vishwajeet Swain, Michael Bremer, Stephen J. Smartt, Joseph P. Anderson, G. C. Anupama, Supachai Awiphan, Sudhanshu Barway, Eric C. Bellm, Sagi Ben-Ami, Varun Bhalerao, Thomas de Boer, Thomas G. Brink, Rick Burruss, Poonam Chandra, Ting-Wan Chen, Wen-Ping Chen, Jeff Cooke, Michael W. Coughlin, Kaustav K. Das, Andrew J. Drake, Alexei V. Filippenko, James Freeburn, Christoffer Fremling, Michael D. Fulton, Avishay Gal-Yam, Lluís Galbany, Hua Gao, Matthew J. Graham, Mariusz Gromadzki, Claudia P. Gutiérrez, K-Ryan Hinds, Cosimo Inserra, Nayana A. J., Viraj Karambelkar, Mansi M. Kasliwal, Shri Kulkarni, Tomás E. Müller-Bravo, Eugene A. Magnier, Ashish A. Mahabal, Thomas Moore, Chow-Choong Ngeow, Matt Nicholl, Eran O. Ofek, Conor M. B. Omand, Francesca Onori, Yen-Chen Pan, Priscila J. Pessi, Glen Petitpas, David Polishook, Saran Poshyachinda, Miika Pursiainen, Reed Riddle, Antonio C. Rodriguez, Ben Rusholme, Enrico Segre, Yashvi Sharma, Ken W. Smith, Jesper Sollerman, Shubham Srivastav, Nora Linn Strotjohann, Mark Suhr, Dmitry Svinkin, Yanan Wang, Philip Wiseman, Avery Wold, Sheng Yang, Yi Yang, Yuhan Yao, David R. Young, WeiKang Zheng. 2023-11-16. Minutes-duration Optical Flares with Supernova Luminosities. https://doi.org/10.1038/s41586-023-06673-6

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