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Title: Search for Lensing Signatures in the Gravitational-Wave Observations from the First Half of LIGO–Virgo’s Third Observing Run
Abstract We search for signatures of gravitational lensing in the gravitational-wave signals from compact binary coalescences detected by Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) and Advanced Virgo during O3a, the first half of their third observing run. We study: (1) the expected rate of lensing at current detector sensitivity and the implications of a non-observation of strong lensing or a stochastic gravitational-wave background on the merger-rate density at high redshift; (2) how the interpretation of individual high-mass events would change if they were found to be lensed; (3) the possibility of multiple images due to strong lensing by galaxies or galaxy clusters; and (4) possible wave-optics effects due to point-mass microlenses. Several pairs of signals in the multiple-image analysis show similar parameters and, in this sense, are nominally consistent with the strong lensing hypothesis. However, taking into account population priors, selection effects, and the prior odds against lensing, these events do not provide sufficient evidence for lensing. Overall, we find no compelling evidence for lensing in the observed gravitational-wave signals from any of these analyses.  more » « less
Award ID(s):
2011334 1921006 2011786 2110460 1806824 1806990 1806577 2110360 1806461 1806656 2110509 1912594 1912630 1912649 1912578 2110575
NSF-PAR ID:
10315581
Author(s) / Creator(s):
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Date Published:
Journal Name:
The Astrophysical Journal
Volume:
923
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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