You cant see a black hole because the gravitational pull of it is so strong that not even light can escape from it. Astronomers find them through observing the space matter that they pull into them, not the hole itself.
specifically, "astronomers" that study black holes are called cosmologists.
Yes, black holes are known and regarded by many scientists, astronomers, and physicists.
Black Holes
Astronomers use evidence such as the behavior of nearby stars and gas, as well as the bending of light around invisible objects, to detect the presence of black holes in space.
Astronomers discover black holes in the universe by observing the effects they have on nearby objects, such as stars and gas. They use telescopes to detect X-rays and other forms of radiation emitted by black holes, as well as studying the gravitational influence they have on surrounding matter.
Astronomers
Astronomers think that the areas around black holes suck everything in like when a tub drains. But black holes are large amounts of matter that is packed into a small area.
Black holes do not emit light, so we cannot observe them directly
Astronomers say that there are several, possibly many, black holes, all a long way from Earth.
Astronomers believe that there are black holes, but I will add that they have only been observed indirectly at great distances, so it may be that the interpretation of our observations will change in the future.
An intermediate-mass black hole is one with a mass significantly greater than the typical stellar-mass black holes, but less than the supermassive black holes such as are found at galactic centers. Their identification remains difficult, and their origins remain in the realm of speculation, although a reasonable theory hints at the likelihood of their formation from accretion of dense stellar clusters... and one possibly is that they are primordial black holes left over from the creation of the universe.
Although the disciplines may overlap with others, it's safe to say that generally astronomers, physicists and astrophysicists study black holes; particle physicists study particles.