Abstract
In recent years, certain luminous extragalactic optical transients have been observed to last only a few days 1. Their short observed duration implies a different powering mechanism from the most common luminous extragalactic transients (supernovae), whose timescale is weeks 2. Some short-duration transients, most notably AT2018cow (ref. 3), show blue optical colours and bright radio and X-ray emission 4. Several AT2018cow-like transients have shown hints of a long-lived embedded energy source 5, such as X-ray variability 6,7, prolonged ultraviolet emission 8, a tentative X-ray quasiperiodic oscillation 9,10 and large energies coupled to fast (but subrelativistic) radio-emitting ejecta 11,12. 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 probably 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.
Original language | English |
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Pages (from-to) | 927-931 |
Number of pages | 5 |
Journal | Nature |
Volume | 623 |
Issue number | 7989 |
Early online date | 15 Nov 2023 |
DOIs | |
Publication status | Published - 30 Nov 2023 |
All Science Journal Classification (ASJC) codes
- General