Observation of gravitational waves from a binary black hole merger

S. E. Hollitt ... D. J. Hosken ... E. J. King ... J. Munch ... D. J. Ottaway ... P. J. Veitch are members of the LIGO Scientific Collaboration and Virgo CollaborationOn September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10^{-21}. It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203 000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410_{-180}^{+160} Mpc corresponding to a redshift z=0.09_{-0.04}^{+0.03}. In the source frame, the initial black hole masses are 36_{-4}^{+5}M_{⊙} and 29_{-4}^{+4}M_{⊙}, and the final black hole mass is 62_{-4}^{+4}M_{⊙}, with 3.0_{-0.5}^{+0.5}M_{⊙}c^{2} radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration