Flexible and Accurate Evaluation of Gravitational-wave Malmquist Bias with Machine Learning
Abstract

Many astronomical surveys are limited by the brightness of the sources, and gravitational-wave searches are no exception. The detectability of gravitational waves from merging binaries is affected by the mass and spin of the constituent compact objects. To perform unbiased inference on the distribution of compact binaries, it is necessary to account for this selection effect, which is known as Malmquist bias. Since systematic error from selection effects grows with the number of events, it will be increasingly important over the coming years to accurately estimate the observational selection function for gravitational-wave astronomy. We employ density estimation methods to accurately and efficiently compute the compact binary coalescence selection function. We introduce a simple pre-processing method, which significantly reduces the complexity of the required machine-learning models. We demonstrate that our method has smaller statistical errors at comparable computational cost than the method currently most widely used allowing us to probe narrower distributions of spin magnitudes. The currently used method leaves 10%–50% of the interesting black hole spin models inaccessible; our new method can probe >99% of the models and has a lower uncertainty for >80% of the models.

Authors:
;
Award ID(s):
Publication Date:
NSF-PAR ID:
10363838
Journal Name:
The Astrophysical Journal
Volume:
927
Issue:
1
Page Range or eLocation-ID:
Article No. 76
ISSN:
0004-637X
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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