Supermassive black holes are some of the most unusual objects in the universe that can help you understand the structure of reality. A team of scientists from the United States conducted a comprehensive study of a black hole in the center of the Galaxy and discovered new phenomena.
Sagittarius A * (Sgr A *) is a supermassive black hole at the center of the Milky Way, located 100 times closer to us than any other of the nearby supermassive black holes. Given this fact, Sgr A * is the main candidate for studying the glow of matter as it accrets into a black hole.
The center of the Galaxy has been observed for decades. Modeling the mechanisms of light variability is a major challenge to our understanding of accretion into supermassive black holes, but it is believed that the relationship between burst times at different wavelengths can reveal information about spatial structure: for example, whether material becomes hotter near a black hole. One of the main obstacles to progress in this matter is the small number of simultaneous observations at different wavelengths.
Astronomers Giovanni Fazio, Joe Hora, Steve Wilner, Matt Ashby, Mark Garvedd, and Howard Smith of the Harvard-Smithsonian Center for Astrophysics and their colleagues conducted a series of multi-wavelength observational campaigns that included the use of the IRAC camera on the Spitzer telescope, the Chandra X-ray Observatory, and See also the ground-based Keck Observatory and the Submillimeter Array (SMA) complex. Their research is described in the Astrophysical Journal. Spitzer was able to continuously observe fluctuations in the black hole for 23.4 hours during each session, which no ground-based observatory can do.
A multi-wavelength view of the region around the galactic center of the Milky Way in X-ray (blue), infrared (red), and optical spectra. Astronomers have measured the events of flares at different wavelengths emanating from the supermassive black hole to its very center.
Computational modeling of radiation near a black hole is a complex work that requires, among other things, simulating the accretion of material, its heating and radiation, as well as the prediction of General Relativity in relation to how this radiation will be seen by an observer (since all this happens near a black hole - probably rotating). Theorists suspect that radiation at shorter wavelengths appears closer to the object, while colder radiation is farther from it. In other words, short wavelength radiation first occurs, followed by long wavelength radiation.
Therefore, the time delay may reflect the distance between these zones. Indeed, in earlier observations, some of which were conducted by the same team, the scientists found that hot near-infrared flares preceded the submillimeter flares seen on the SMA. In their work, the researchers report two flares that probably violate these and other obvious patterns: the first event occurred simultaneously at all wavelengths, in the second - X-ray, near-infrared and submillimeter flares occurred with an hour difference, that is, not quite simultaneously, but all very close to each other. New observations will expand in future concurrent campaigns.
Vladimir Gil
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