The Event Horizon Telescope (EHT) collaboration has shown the first image of the shadow of a supermassive black hole in galaxy M87 in polarized light. Astronomers were able to determine the strength of the magnetic field near the black hole and build a picture of the field lines of the field, as well as find out the parameters of the plasma.
The EHT (Event Horizon Telescope) is a global ultra-long baseline radio interferometer consisting of eight observatories and operating at a wavelength of 1.3 millimeters.
By synchronizing the operation of individual telescopes using atomic clocks and using supercomputers for data processing, the project was able to achieve its main goal. For the first time in history, to obtain an image of the shadow of a supermassive black hole in the center of the active elliptical galaxy M87 and even see its oscillations.
In addition, scientists were able to view a distant blazar – 3C 279. It is expected that as the project develops and new telescopes are included in its composition, astronomers will be able to expand the operating wavelength range and obtain an image of the shadow of a supermassive black hole at the center of the Milky Way.
New papers published by the EHT collaboration describe the results of the analysis of polarimetric observations of the black hole of the M87 galaxy in April 2017.
Polarized synchrotron radiation carries information about the configuration of the magnetic field and the properties of magnetized plasma near the black hole, which makes it possible to test the models of accretion of matter onto the black hole and the mechanisms of formation of a relativistic jet.
As a result, astronomers have captured the first polarized image of the shadow of a supermassive black hole in M87. The researchers were able to determine the average electron density of the plasma in the emitting region near the black hole, equal to 10 4-7 particles per cubic centimeter.
They also measured the magnetic field strength, equal to 1–30 gauss, and the electron temperature of the plasma equal to (1–12) × 10 10 kelvin. In addition, scientists were able to estimate the average accretion rate of matter onto a black hole, equal to (3–20) × 10 -4 solar masses per year.
According to them, the observational data are best described by a magnetohydrodynamic model of a strongly magnetized plasma, which indicates the important role magnetic field in the immediate vicinity of a black hole during the formation of a relativistic jet.
This discovery will help scientists to finally understand the behavior of matter in the regions adjacent to a black hole, in this case, M87. This is something that has been researched for decades and yet, the first image of the shadow of a black hole was captured and revealed only now.
Join the discussion and participate in awesome giveaways in our mobile Telegram group. Join Curiosmos on Telegram Today. t.me/Curiosmos
• Collaboration, T., Akiyama1, K., Algaba4, J., Alberdi5, A., Alef6, W., Anantua3, R., . . . Https://orcid.org/0000-0002-9774-3606, S. (2021, March 24). First M87 Event Horizon Telescope Results. VII. Polarization of the Ring.
• Collaboration, T., Akiyama1, K., Algaba4, J., Alberdi5, A., Alef6, W., Anantua3, R., . . . Https://orcid.org/0000-0002-9774-3606, S. (2021, March 24). First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon.
• ESO. (n.d.). Astronomers image magnetic fields at the edge of m87’s black hole.