The astrophysical odds of GW151216
Abstract
The gravitationalwave candidate GW151216 is a proposed binary black hole event from the first observing run of the Advanced LIGO detectors. Not identified as a bona fide signal by the LIGOVirgo collaboration, there is disagreement as to its authenticity, which is quantified by p_{astro}, the probability that the event is astrophysical in origin. Previous estimates of p_{astro} from different groups range from 0.18 to 0.71, making it unclear whether this event should be included in population analyses, which typically require p_{astro} > 0.5. Whether GW151216 is an astrophysical signal or not has implications for the population properties of stellarmass black holes and hence the evolution of massive stars. Using the astrophysical odds, a Bayesian method that uses the signal coherence between detectors and a parametrized model of nonastrophysical detector noise, we find that p_{astro} = 0.03, suggesting that GW151216 is unlikely to be a genuine signal. We also analyse GW150914 (the first gravitationalwave detection) and GW151012 (initially considered to be an ambiguous detection) and find p_{astro} values of 1 and 0.997, respectively. We argue that the astrophysical odds presented here improve upon traditional methods for distinguishing signals from noise.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 October 2020
 DOI:
 10.1093/mnras/staa2332
 arXiv:
 arXiv:2006.05039
 Bibcode:
 2020MNRAS.498.1905A
 Keywords:

 gravitational waves;
 Astrophysics  High Energy Astrophysical Phenomena;
 General Relativity and Quantum Cosmology
 EPrint:
 6 pages, 1 figure, 1 table, publised in MNRAS