Frank Herrmann - Postdoctoral Scholar
301D Whitmore Laboratory
Binary Black Hole Simulations
I work in the field of numerical relativity with a focus on the study of collisions of two black holes (binary black hole problem). Good observational evidence for black holes exist in two very different mass ranges: stellar mass black holes moving in galaxies and supermassive black holes with masses of 105 to 1010 (hundreds of thousands to tens of billions) ofsolar masses.
When black holes collide they emit gravitational radiation which earth based gravitational wave detectors like LIGO, GEO600, VIRGO and TAMA are searching for. These earth based detectors will be most sensitive for stellar mass mergersand for decent detection chances accurate waveform templates are needed.
In an unequal-mass black hole merger the anisotropic emission of gravitational waves will lead to a kick on the merger remnant. In the case of supermassive black holes the size of the kick will determine if the remnant remains in the merged galaxy or leaves. Determining the kick has therefore important consequences for galactic mergerscenarios.
We have performed first studies of unequal-mass black holes. The figure shows the apparent horizon mass vs. time. Initially there are two separated black holes with different masses (mass ratio q=m1/m2) which then merge into a final single black hole.