MOSCOW, 28 Mar. A Russian space telescope and a scientific instrument aboard an American spacecraft were able to investigate the gamma-ray burst that occurred in October 2022, blinding other devices that observed it, the Space Research Institute (IKI) of the Russian Academy of Sciences reported.
«The Russian X-ray telescope ART-XC named after M.N. Pavlinsky of the Spektr-RG observatory and the Russian Konus instrument aboard the WIND (NASA) spacecraft studied the gamma-ray burst GRB 221009A — the brightest of the gamma-ray bursts registered by the Konus» for almost 30 years of its continuous operation and, perhaps, the brightest gamma-ray burst in the history of mankind,» the institute said in a statement on its website.
It is noted that detailed observations over a wide range of wavelengths have shown that the most likely source of the gamma-ray burst was a massive star that «collapsed» into a black hole. However, many features of this process and the physics of the burst itself still require additional studies.
The gamma-ray burst GRB 221009A occurred on October 9, 2022. As the scientists said, it turned out to be so powerful that it «blinded» most of the cosmic gamma-ray detectors. The institute explained that the detectors «choked» with the number of photons that came to them, and could not count them. Only a few coped with this task, including two domestic instruments.
The Russian instrument «Konus» aboard the WIND spacecraft and the Russian telescope ART-XC aboard the space observatory «Spektr-RG» are located at the Lagrange points (where the mutual influence of the Sun and the Earth is balanced). WIND «hangs» at point L1 1.5 million kilometers from the Earth towards the Sun, and ART-XC — at the same distance, but on the other side of the Earth.
The «cone» was also initially «blinded» by a strong gamma-ray burst. However, thanks to the experience accumulated over almost 30 years of the experiment, the parameters of this gamma-ray burst were restored. In particular, this was helped by joint work with ART-XC.
«We were able to reconstruct the event's light curve, confirmed by independent ART-XC observations, and determine the colossal energy released by the burst source in just a few minutes. It exceeds 1055 erg (equivalent to more than 6.5 solar rest masses). This made GRB 221009A the brightest a gamma-ray burst among more than 3,500 similar events recorded since the start of the Cone in 1994, ”the Institute quotes the words of the scientific director of the Cone, Dmitry Frederiks.
The ART-XC telescope named after M. N. Pavlinsky registered the gamma-ray burst indirectly, because at that moment it was «looking» not in its direction. In the body of the telescope, under the action of a gamma-ray burst, a secondary X-ray flux was generated. Due to this, its power weakened and the sensitive ART-XC detectors were able to reliably measure the true brightness parameters of GRB 221009A.
According to various scientists, gamma-ray bursts of this power can be observed on Earth once every ten thousand years. At the same time, not all features of the phenomenon have been reliably studied. Usually, when a star collapses into a black hole, a supernova explosion should occur in its place. However, no such outbreak occurred. Scientists suggest that this may be due to the fact that the event happened in an area with a lot of dust that absorbed the radiation. Or there was no supernova at all, if all the matter of the star was «packed» into a black hole.