The movement of gas around a supermassive black hole in a distant quasar helps determine its mass

Astronomers used the ground-based interferometer VLTI to measure the mass of a supermassive black hole in a quasar that took 11 billion years for light to reach Earth. Its mass, he estimated, was 320 million solar masses, significantly less than expected based on the mass of its parent galaxy. This suggests that the growth of black holes is slower than that of surrounding galaxies. This paper was published in the journal Nature. Observations of galaxies in the local universe containing supermassive black holes show that they are coevolving. The main mechanism explaining this relationship is the effect on the star formation rate of the active core, where the black hole absorbs matter and causes an outflow of matter and energy from the center of the galaxy. One of the important areas of research on the relationship between black holes and galaxies is the cosmic noon that experienced active star formation and black hole growth 8 to 12 billion years ago (redshifts z = 1 to 3). Observation of galaxies that existed. . A team of astronomers led by Robert Abter of the European Southern Observatory has announced their measurements of the mass of the supermassive black hole at z = 2.32 in the bright quasar SDSS J092034.17+065718.0 (or J0920). Researchers used the GRAVITY+ instrument and the ground-based interferometer VLTI, a combination of four 8-meter VLT telescopes, to track the velocity of gas moving near the black hole and compare observations to kinematic models. and estimated the mass of the black hole. . J0920 is one of the brightest quasars with a redshift of z~2. This is easily observed in the thick, moderately tilted disk of gas around a 3.2 x 108 solar mass black hole that accumulates material in a super-Eddington mode. In this case, the stellar mass of the parent galaxy is 6 × 1011 solar masses. Therefore, it may have grown faster than the black hole, suggesting that there is a lag between galaxy formation and the black hole.

J0920’s black hole is unlikely to continue accreting matter at a very high rate for a long time (107 years) until it becomes an early (elliptical or lenticular) galaxy in the local universe. Most likely, episodes of galactic nuclear activity last longer (108 years) and are characterized by moderate accretion rates.

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