It seems that there are more than one ways to spot black holes.
A stellar-mass black hole is a compact object with a mass that’s greater than three solar masses together. It is so dense and has such a powerful force of attraction that light is not able to escape from it.
Black holes cannot be observed directly, but only through their secondary effects. For instance, you can see a black hole feeding on a star.
When matter falls onto a black hole, it does so quietly, but this does not mean that there aren’t periods when the infall is violent and bursts, leading to the production of an intense outburst of an x-ray brightness.
Binary systems that are composed of a star donating mass to a black hole are essential labs for understanding the most extreme physical phenomena in the universe such as the collapse of a massive star into a black hole or a neutron star.
“Until now, some 60 candidates for this type of black hole have been found in the Milky Way via the detection of transient eruptions of X-rays, but only 17 of these have been confirmed,” reports Phys.org.
Researchers only have limited knowledge of the formation and evolution of black holes.
A new way to spot black holes
The IAC researchers Jorge Casares, and Miguel A. Pérez Torres have tested a new technique measuring the brightness of these binary pairs with a combination of filters centered on the line of hydrogen H-alpha.
Such measurements give information about the intensity and the width of this line which forms in the accretion disc that can be seen around the black hole.
The width of H-alpha can be used as an indicator showing the strength of the gravitational field, and it can be used as a hint of the presence of the black hole. It seems that this technique can be used to reveal new black hole binaries in an inactive phase.
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Rada attended the courses in the Faculty of Letters, Romanian-English section, and finished the Faculty of Theatre and Television, Theatrical Journalism section, both within the framework of Babeş-Bolyai University of Cluj-Napoca. Up till now, she reviewed books, movies, and theatre-plays, enjoying subjects from the cultural niche. Her experience in writing also intersects the IT niche, given the fact that she worked as a content editor for firms that produce software for mobile devices. She is collaborating with online advertising agencies, writing articles for several websites and blogs.