Amazing stuff!
"... when they detected an extraordinary flash in a part of the sky where no such light had been observed the night before. From a rough calculation, the flash appeared to give off more light than 1,000 trillion suns. ...
Over the next few days, multiple telescopes focused in on the signal to gather more data across multiple wavelengths in the X-ray, ultraviolet, optical, and radio bands, to see what could possibly produce such an enormous amount of light.
Now, the ... astronomers ... have determined a likely source for the signal. ... the scientists report that the signal, named AT 2022cmc, likely comes from a relativistic jet of matter streaking out from a supermassive black hole at close to the speed of light. They believe the jet is the product of a black hole that suddenly began devouring a nearby star, releasing a huge amount of energy in the process. ...
Astronomers have observed other such “tidal disruption events,” or TDEs, in which a passing star is torn apart by a black hole’s tidal forces. AT 2022cmc is brighter than any TDE discovered to date. The source is also the farthest TDE ever detected, at some 8.5 billion lights years away — more than halfway across the universe. ...
AT 2022cmc is the fourth Doppler-boosted TDE ever detected and the first such event that has been observed since 2011. It is also the first TDE discovered using an optical sky survey. ..."
Astronomers have observed other such “tidal disruption events,” or TDEs, in which a passing star is torn apart by a black hole’s tidal forces. AT 2022cmc is brighter than any TDE discovered to date. The source is also the farthest TDE ever detected, at some 8.5 billion lights years away — more than halfway across the universe. ...
AT 2022cmc is the fourth Doppler-boosted TDE ever detected and the first such event that has been observed since 2011. It is also the first TDE discovered using an optical sky survey. ..."
"... And on February 11 this year [2022] it spotted an ... incredibly bright spot of light flared up in an area where there’d been nothing the night before. ..."
From the abstract:
"A black hole can launch a powerful relativistic jet after it tidally disrupts a star. If this jet fortuitously aligns with our line of sight, the overall brightness is Doppler boosted by several orders of magnitude. Consequently, such on-axis relativistic tidal disruption events have the potential to unveil cosmological (redshift z > 1) quiescent black holes and are ideal test beds for understanding the radiative mechanisms operating in super-Eddington jets. Here we present multiwavelength (X-ray, UV, optical and radio) observations of the optically discovered transient AT 2022cmc at z = 1.193. Its unusual X-ray properties, including a peak observed luminosity of ≳1048 erg s−1, systematic variability on timescales as short as 1,000 s and overall duration lasting more than 30 days in the rest frame, are traits associated with relativistic tidal disruption events. The X-ray to radio spectral energy distributions spanning 5–50 days after discovery can be explained as synchrotron emission from a relativistic jet (radio), synchrotron self-Compton (X-rays) and thermal emission similar to that seen in low-redshift tidal disruption events (UV/optical). Our modelling implies a beamed, highly relativistic jet akin to blazars but requires extreme matter domination (that is, a high ratio of electron-to-magnetic-field energy densities in the jet) and challenges our theoretical understanding of jets."
The Birth of a Relativistic Jet Following the Disruption of a Star by a Cosmological Black Hole (no public access)
Fig. 1: AT 2022cmc’s X-ray evolution on various timescales at different epochs. (Nature Astronomy only provides these low resolution images! Very regrettable!)
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