Grazing Collisions of Black Holes via the Excision of Singularities

We present the first simulations of non-head-on (grazing) collisions of binary black holes in which the singularities are excised from the simulation. Initially equal mass m black holes (spinning or not) are separated by ~10m and with impact parameter ~2m. Evolutions to t~35m are obtained where two separate horizons are present for t~3.8m then a single enveloping horizon forms indicating that the holes merged. Apparent horizon area estimates suggest gravitational radiation of about 2%-3% of the total mass. The evolutions end after a moderate amount of time because of instabilities.