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Astronomers Have Found The Brightest X-Ray Quasar With A Large Redshift

Astronomers Have Found The Brightest X-Ray Quasar With A Large Redshift

Using the Spectrum-RG Observatory, astronomers discovered that the quasar CFHQSJ142952+544717 emits very strongly in the x-ray range-so much so that it makes it the brightest x-ray quasar of all with a large redshift. A Preprint of the article is available on the website

Quasars are one of the brightest objects in the visible Universe. They are very distant galaxies with a supermassive black hole in the center that actively absorbs the surrounding matter. The more intense the accretion processes, the brighter the quasar, i.e. the more photons it emits.

Many quasars are so far away from us that we can see the light that was emitted by them at a time when only a few billion years have passed since the Big Bang. Astronomers are particularly interested in objects with a redshift of z > 6.0 because they can help us study the processes that took place in the young Universe and learn about the evolution of quasars.

Pavel Medvedev (P. Medvedev) from the space research Institute of the Russian Academy of Sciences together with colleagues found that one of the known quasars with strong radiation in the radio range, CFHQSJ142952+544717, also emits powerfully in the x-ray range compared to other similar objects. Its luminosity in the x-ray was approximately 2.6×1046 erg per second. Given that the redshift of quasar z is equal to 6.18 — this is the brightest x-ray quasar with a redshift greater than 6.

The bolometric luminosity of CFHQSJ142952+544717 was from 2×1047 to 3×1047 erg per second. Based on this data, astronomers were able to estimate the mass of the central black hole, which turned out to be one and a half billion times the mass of the Sun.

Astronomers suggest that the greater brightness of the quasar's x-ray radiation compared to optical and ultraviolet radiation may be due to its radio loudness — in particular, to the contribution of reverse Compton scattering of photons of background microwave radiation on relativistic jet electrons. In this case, CFHQSJ142952+544717 may be one of many quasars with strong radiation in the radio band, which also has a large x-ray brightness.

The Spectrum-RG x-ray Observatory, thanks to which the discovery was made, started its main scientific program only at the end of last year. In June, the German eROSITA telescope on Board completed the first survey of the sky in the soft x-ray range.