GW150914: First results from the search for binary black hole   coalescence with Advanced LIGO
  On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) simultaneously observed the binary black hole merger GW150914. We report the results of a matched-filter search using relativistic models of compact-object binaries that recovered GW150914 as the most significant event during the coincident observations between the two LIGO detectors from September 12 to October 20, 2015. GW150914 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 5.1 {\sigma}. 
The LIGO Scientific Collaboration and the Virgo Collaboration: B. P.   Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. ...
gr-qc astro-ph.HE astro-ph.IM