In the “black hole” family, they have so far been missing. A team of astrophysicists from the University of Melbourne announced, Monday, March 29, 2021, the probable discovery of the first black hole of intermediate mass: 55,000 solar masses. A feat, because these stars predicted by the models had so far escaped the various detection methods. Whether these are used for stellar black holes (up to a hundred solar masses), or for super massive black holes (a few hundred thousand to a few billion solar masses). In fact, the researchers had to be cunning to flush out this cosmic version of Arlésienne …
Too light, or too heavy
This category of black holes is difficult to find because they are in a middle ground. Stellar black holes, when they turn around, form gravitational waves picked up by the Virgo detectors in Italy and Ligo in the United States. A dance of this type is recorded almost every month now, but the protagonists usually do a few dozen solar masses. Super massive black holes, on the other hand, swallow up matter (gas clouds, stars, and anything that passes within their reach) from their lair, usually in the center of galaxies. The matter tormented by the force of attraction of the giant black hole emits a large amount of energy, making the star as visible as a beacon to scientists’ instruments. While an intermediate black hole is too massive to form gravitational waves of a frequency accessible to detectors. And if it does not devour matter, which can happen to it if it is isolated, it is totally invisible.
A mirage caused by a black hole
To find this intermediate black hole, the researchers searched the archives, more exactly those of the BATSE detector (Burst and Transient Source Experiment), of the American satellite Compton Gamma Ray Observatory, in service between 1991 and 2000. It records[…]
Read more on sciencesetavenir.fr
Get the latest news delivered to your inbox
Follow us on social media networks