Giant black holes can kill galaxies!

Decades have passed since then Astronomy scientistsAstronomy scientists Note that some galaxies are almost empty of them cloudsclouds Of molecular and dusty gases, this specifically means reservoirs where CollapsesCollapses Gravity Star Nurseries. Theorists are trying to understand what could have “killed” these galaxies, and some have put forward the idea, supported by calculations and observations, that the culprits must be the galaxies. Supermassive black holesSupermassive black holes It contains one million to several billion times the mass of the Sun which we now know is likely to be found at the core of all large galaxies.

When these black holes are fed by large streams of matter falling on them for whatever reason, or filaments of cold dark matter or merging with a galaxy after a collision, the matter is greatly heated to form something similar to dark matter. Accumulation diskAccumulation disk About giant black holes, which also orbit. We get plasma and jets of matter, as well as a radiation flux that pressurepressure It can resist falling streams of molecular matter toward the black hole. The radiation is so intense that we get clearly visible cosmic beacons billions of miles away.Light yearLight year They radiate like all the stars of one large galaxy: the quasars.

And this is the idea: Radiation pressureRadiation pressure It can be very important, such as flow Solar windSolar wind On the tail of A CometCometThey eject molecular gas from the interstellar medium into galaxies beyond them. They then find themselves deprived of materials that can be used to birth new stars and galaxies “die”, unless they are replenished with gas. This is further evidence of the existence of this phenomenon by a team of researchers led by Assistant Professor Dragan Salak (Hokkaido University), Assistant Professor Takuya Hashimoto (University of Tsukuba), and Professor Akio Inoue (Waseda University).

First evidence of the suppression of star formation due to quasars in the early universe

Press release from Hokkaido University accompanying the publication of the team's work in Astrophysical Journal (The article on this topic is available for free at arXiv) until he explains that ” First evidence for the suppression of star formation caused by the flow of molecular gas in a host galaxy QuasarQuasar in'beingbeing Primitive “. Obtained through the famous network Radio telescopesRadio telescopes Phones act as a giant pain instrument (Atacama Large Millimeter/Submillimeter Array) in Chile, through a careful study of a galaxy containing a quasar called J2054-0005.

Dragan Salak Explain that” Theoretical work suggests that outflows of molecular gas play an important role in the formation and evolution of galaxies from an early age, because they can regulate star formation. Quasars are particularly energy sources, so we expected them to be able to generate powerful outflows “.

His colleague Hashimoto specifies that “ J2054-0005 is one of the brightest quasars in the distant universe, so we decided to target this object as an excellent candidate to study it. But only Alma was sensitive and… Frequency rangeFrequency range Enough to detect the molecular flow that gave rise to the quasars observed in the distant early universe.

In the same Hokkaido University press release, Dragan Salak reveals the method he uses AstrophysicistsAstrophysicists To achieve their goal: The outgoing molecular gas (OH) was discovered by AbsorptionAbsorption. This means that we have not observed microwave radiation coming directly from space MoleculesMolecules oh; Instead, we observed radiation coming from the bright quasar – and absorption means that the OH molecules absorbed some of the quasar's radiation. So it was like detecting the presence of a gas by seeing the “shadow” it casts in front of a light source “.