Observing gravitational-wave transient GW150914 with minimal assumptions

The recent announcement by LIGO of the detection of the gravitational-wave signal GW150914 has ignited tremendous interest. The two manuscripts highlighted here detail the impressive analysis performed by LIGO to identify a specific black hole binary merger as the source of GW150914. The papers describe two independent methods of analysis: the matching of the signal to numerical-relativity-generated templates and unmodeled burst analyses. The two papers together provide detailed and virtually incontrovertible evidence, by the standards of experimental physics, of the detection of gravitational waves generated by a merger of a black hole binary system consisting initially of black holes of approximately 36 and 29 solar masses.