Gravitational radiation is properly defined only at future null infinity (\scri), but in practice it is estimated from data calculated at a finite radius. We have used characteristic extraction to calculate gravitational radiation at \scri for the inspiral and merger of two equal mass non-spinning black holes. Thus we have determined the first unambiguous merger waveforms for this problem. The implementation is general purpose, and can be applied to calculate the gravitational radiation, at \scri, given data at a finite radius calculated in another computation.
@article{arxiv.0907.2637,
title = {Unambiguous determination of gravitational waveforms from binary black hole mergers},
author = {C. Reisswig and N. T. Bishop and D. Pollney and B. Szilagyi},
journal= {arXiv preprint arXiv:0907.2637},
year = {2010}
}