Eight New Echoing Black Holes Discovered in Our Galaxy: MIT Researchers
Black holes are fascinating and mysterious objects. They are also very afraid, because their gravity is so strong that they do not allow anything to pass through them, not even light, except in rare cases when they are foraging. When a black hole sucks in gas and dust from an orbiting star, it creates spectacular X-ray bursts that bounce back and spiral inward. During this phase, the posterior hole illuminates its surroundings. Researchers from MIT have now found eight new echoing black hole binaries – systems with a star orbiting and sometimes being eaten by a black hole – in our Milky Way. Previously, only two were known.
The researchers looked for flashes of lightning and echoes from nearby black hole X-ray binaries, using a new automated search engine, called “Echophone”. This study is supported in part by NASA.
By comparing the echoes, they created a general picture of how a black hole develops in an explosion. They discovered the first black hole to undergo a “hard” state, creating a halo of high-energy photons along with a jet of relativistic particles that are blasted away at close to the speed of light. . A final high-energy flash is emitted by the black hole at a certain point. Then the system enters a low power (soft) state.
This final flash may indicate that the black hole’s halo lasts for a short time before disappearing completely. Findings, published in the Astrophysical Journal, may help explain how the more massive supermassive black holes at the center of a galaxy shape its formation.
“The role of black holes in galactic evolution is an outstanding question in modern astrophysics,” speak Erin Kara, assistant professor of physics at MIT, in a statement. By understanding outbursts in these small black hole binaries, Kara said, they hope to understand how similar outbursts in supermassive black holes affect their native galaxies. .
For their research, the team selected 26 black hole X-ray binary systems known to emit X-ray bursts. Of these, the team found that 10 systems systems are close and bright enough that they can distinguish X-ray echoes between bursts. Eight out of 10 have never been known to resonate before.