Mason Professor and Alumnus Discover Smallest Black Hole to Date

Posted: April 11, 2008 at 1:00 am, Last Updated: November 30, -0001 at 12:00 am

By Tara Laskowski

Lev Titarchuk
Lev Titarchuk

Mason scientist Lev Titarchuk, professor of computational and data sciences, and his former PhD student and Mason alumnus, Nikolai Shaposhnikov, recently developed a new sophisticated technique to closely measure the mass of black holes.

Their technique, which has been proven on numerous other known black holes, is now being used to detect unusually small black holes.

At a recent meeting of the American Astronomical Society’s High Energy Astrophysics Division, Shaposhnikov and Titarchuk presented their discovery of a new mini black hole — “mini” in that it is just 15 miles across and 3.8 times the mass of our sun.

This is a huge contrast to the black hole at the center of our Milky Way galaxy, whose mass is about 3.7 million times the mass of our sun.

“This black hole is really pushing the limits,” said Shaposhnikov, a scientist for NASA’s Goddard Space Flight Center, during a press conference at the meeting.

“For many years astronomers have wanted to know the smallest possible size of a black hole, and this little guy is a big step toward answering that question.”

The technique they developed for weighing looks at the relationship between a black hole and the surrounding disk of matter spiraling into it, called an accretion disk. Gas orbiting in these disks eventually falls into the black hole.

As particles in the accretion disk get closer to the black hole, they build up and crash into each other in a way that Titarchuk likens to a car accident or traffic jam.

He determined that the distance from the black hole to the accretion disk is on a direct scale with the mass of the black hole.

Using these proportions and the oscillation frequency of particles in the accretion disk he is able to “weigh” a black hole with a very small margin of error.

Titarchuk says he is pleased with the accuracy of their technique and plans to continue studying black holes both within and outside the galaxy.

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