In the center of the Milky Way, unusual outbreaks were noted

In the center of the galaxy observed for decades.

Sagittarius a * (Sgr A *) is a supermassive black hole located in the center of the Milky Way, located 100 times closer than any other supermassive black hole nearby. Given this fact, Sgr A * is a prime candidate for studying the luminescence of a substance during its accretion in a black hole.

Modeling the mechanisms of light variability is a major challenge to understanding accretion in supermassive black holes, but it is thought that the relationship between eruption time at different wavelengths may reveal information about structure space: for example, if the warmer material near a black hole. One of the main obstacles to promoting this issue is the scarcity of simultaneous observations at different wavelengths.

Astronomers Giovanni Fazio, Joe Hora, Steve Wilner, Matt Ashby, Mark Carved and Howard Smith of the Harvard-Smithsonian Astrophysical Center, along with their colleagues, conducted a series of multi-length observation campaigns involving the use of the IRAC camera on the Spitzer telescope, the Chandra X-ray observatory, as well as the Keck terrestrial observatory and the network submillimeter complex (SMA). Their research described in the journal Astrophysical. "Spitzer" could constantly monitor fluctuations in the black hole for 23.4 hours during each session, which would not create a terrestrial observatory.

Multi-wavelength view of the region around the galactic center of the Milky Way in X-ray (blue), infrared (red) and optical spectra. Astronomers measured the events of eruptions at different wavelengths emanating from a supermassive black hole in the center. © X-ray: NASA / CXC / UMass / D.

Computer modeling of radiation near a black hole is a complex task that requires, among other things, simulations of the accretion of the material, its heating and its radiation, as well as predictions of relativity general in terms of the perception of observation by this radiation. (since all this is happening near a black hole is probably spinning). Theorists suspect that the emission at shorter wavelengths appears closer to the object and that a colder radiation is already far from it. In other words, the first is short-wave radiation followed by long-term radiation.

Therefore, the delay may reflect the distance between these areas. Indeed, in previous observations, some of which belonged to the same team, the researchers found that the process of alloying hot flashes preceded the submillimetric eruptions seen in the AMS. In their article, the researchers report that two outbreaks probably violate these models and other obvious ones: the first event occurred simultaneously at all wavelengths, and the outbreaks of the second X-ray and processing of the alloy sub-millimeter measurements occurred in one hour, which is not quite the case. idem but still very close to each other. New observations will be expanded in future simultaneous campaigns.