Figure 2. [CC BY 3.0 (https://creativecommons.org/licenses/by/3.0/)], Published in article 'Observation of Gravitational Waves from a Binary Black Hole Merger' by B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration), in Physical Review of Letters, 116, 061102 – Published 11 February 2016. American Physical Society. DOI: 10.1103/PhysRevLett.116.061102