Constraining the Lensing of Binary Black Holes from Their Stochastic Background

Moore, C. J.; Pratten, G.; Schmidt, P.; Bianconi, Matteo; Vecchio, A.

doi:10.1103/physrevlett.125.141102

Cited by 32 publications

(22 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here we briefly comment that this conclusion is derived from a model that assumes as prior information that lensing is not taking place. [1] follows the work of [10], but in that reference (as well as in [1]) the model that is being constrained is normalized to the observed local rate. This implicitly assumes that none of the observed events are lensed, but also that the contribution of the local universe (z < 0.3) to the stochastic background is significant.…”

Section: Stochastic Backgroundmentioning

confidence: 99%

Evidence for lensing of gravitational waves from LIGO-Virgo

Diego,

Broadhurst,

Smoot

2021

Preprint

View full text Add to dashboard Cite

Recently, the LIGO-Virgo Collaboration (LVC) concluded that there is no evidence for lensed gravitational waves (GW) in the first half of the O3 run [1], claiming "We find the observation of lensed events to be unlikely, with the fractional rate at µ > 2 being 3.3 × 10 −4 ". While we agree that the chance of an individual GW event being lensed at µ > 2 is smaller than < 10 −3 , the number of observed events depends on the product of this small probability times the rate of mergers at high redshift. Observational constraints from the stochastic GW background indicate that the rate of conventional mass BBH mergers (8 < M/M < 15) in the redshift range 1 < z < 2 could be as high as O(10 7 ) events per year, more than sufficient to compensate for the intrinsically low probability of lensing. To reach the LVC trigger threshold these events require high magnification, but would still produce up to 10 to 30 LVC observable events per year. Thus, all the LVC observed ordinary stellar mass BBH mergers from this epoch must be strongly lensed in addition up to 10 6 more events would be below threshold. By adopting low-rates at high redshift, LVC assumes that lensed events can not be taking place, thus incorrectly assigning them a closer distance and higher masses by a factor of a few (typically 2 to 5). The LVC adopted priors on time delay are in tension with the distribution of observed time delays in lensed quasars. Pairs of events like GW190421 213856-GW190910 112807 and GW190424 180648-GW190910 112807, which are directly assigned a probability of zero by LVC, should be instead considered as prime candidates to be strongly lensed GW pairs, since their separation in time is consistent with observations of time delays in lensed quasars. Correcting for the LVC wrong Bayesian priors -maximum merger rate of conventional mass BBH in 1 < z < 2, and gravitational lensing time-delay model, reverses the LVC conclusions and supports the strong gravitational lensing hypothesis for a significant fraction of the lensed candidates identified by LVC.

show abstract

Section: Stochastic Backgroundmentioning

confidence: 99%

Evidence for lensing of gravitational waves from LIGO-Virgo

Diego,

Broadhurst,

Smoot

2021

Preprint

View full text Add to dashboard Cite

show abstract

“…The rate of lensing can also be inferred from the stochastic GW background (SGWB; Buscicchio et al 2020aBuscicchio et al , 2020bMukherjee et al 2021a). Thus, we use the non-observation of strong lensing and the stochastic background to constrain the BBH merger-rate density and the rate of lensing at high redshifts.…”

Section: Introductionmentioning

confidence: 99%

Search for Lensing Signatures in the Gravitational-Wave Observations from the First Half of LIGO–Virgo’s Third Observing Run

Abbott

Abraham

et al. 2021

ApJ

View full text Add to dashboard Cite

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.

show abstract

“…As was recently pointed out in Refs. [249][250][251], these inferences about the BBH merger rate at high redshift can also be used to set an upper bound on the fraction of individual detections that are expected to undergo strong gravitational lensing.At present (i.e., post-O3), the uncer-tainty on Ṅ(z) is still large, spanning several orders of magnitude at redshifts z 1 [56], but we can look forward to significant improvements with future LVK observing runs. The inferred redshift shape of Ṅ(z) is currently consistent with the BBH merger rate directly tracking the cosmic star formation rate (see Figure 10), but there are some tentative hints of a shallower growth at low redshift, as one would expect if there is a non-zero delay time between star formation and the eventual merger event.…”

Section: Search Results For An Isotropic Background By Lvkmentioning

confidence: 99%

Stochastic Gravitational-Wave Backgrounds: Current Detection Efforts and Future Prospects

et al. 2022

View full text Add to dashboard Cite

The collection of individually resolvable gravitational wave (GW) events makes up a tiny fraction of all GW signals that reach our detectors, while most lie below the confusion limit and are undetected. Similarly to voices in a crowded room, the collection of unresolved signals gives rise to a background that is well-described via stochastic variables and, hence, referred to as the stochastic GW background (SGWB). In this review, we provide an overview of stochastic GW signals and characterise them based on features of interest such as generation processes and observational properties. We then review the current detection strategies for stochastic backgrounds, offering a ready-to-use manual for stochastic GW searches in real data. In the process, we distinguish between interferometric measurements of GWs, either by ground-based or space-based laser interferometers, and timing-residuals analyses with pulsar timing arrays (PTAs). These detection methods have been applied to real data both by large GW collaborations and smaller research groups, and the most recent and instructive results are reported here. We close this review with an outlook on future observations with third generation detectors, space-based interferometers, and potential noninterferometric detection methods proposed in the literature.

show abstract

Constraining the Lensing of Binary Black Holes from Their Stochastic Background

Cited by 32 publications

References 48 publications

Evidence for lensing of gravitational waves from LIGO-Virgo

Evidence for lensing of gravitational waves from LIGO-Virgo

Search for Lensing Signatures in the Gravitational-Wave Observations from the First Half of LIGO–Virgo’s Third Observing Run

Stochastic Gravitational-Wave Backgrounds: Current Detection Efforts and Future Prospects

Contact Info

Product

Resources

About