'Doughnuts' are gas fountains of Back hole.
Based on computer simulations and new observations from Atacama Large Millimeter/sub millimeter Array (ALMA) in Chile ,researchers have concluded that the gas expelled from the center interacts will in falling gas to dynamic circulation pattern similar to fountains.Most galaxies host a super massive black hole ,millions or billions of times as heavy as the sun , in their center.
Some of these black holes swallow materials quite actively.However , astronomers have believed rather than falling directly into black hole ,matter instead builds up around the active black hole forming a drought structure.
Takuma Izumi , a reaearcher at the National Astronomical Observatory of Japan(naoj),led a team astronomers they used Alma to observe the supermassive bl;ack hole in the Circinus Galaxy located 14 million light away from the Earth in the direction of the constellation Circinus.
The team then compared their observations to a computer simulation of gas falling towards a black hole made with the Cray XC30 ATERUI super ompter operated by NAOJ.
This comparison revealed that the presumptive ‘’doughnut” is not actually a rigid structure , but ,but instead a complex collection of highly dynamic gaseous components.
First, cold molecular gas falling towards the black hole forms a disk near the plane of rotation.As it approaches the black hole, this gas is heated until the molecules breakdown into the component atoms and ions.Some of these atoms are then expelled above ans below the disk,rather than being absorbed by the black hole.
This hot atomic gas falls back onto the disk creating a turbulent three dimensional structure.