What if LIGO’s gravitational wave detections are strongly lensed by massive galaxy clusters?

Research output: Contribution to journalArticlepeer-review


  • Mathilde Jauzac
  • Richard Massey
  • Johan Richard

Colleges, School and Institutes


We explore the possibility that the gravitational waves (GWs) detected in 2015 were strongly-lensed by massive galaxy clusters. We estimate that the odds on one of the GWs being strongly-lensed is $10^5:1$, taking in to account the binary black hole merger rate, the gravitational optics of known cluster lenses, and the star formation history of the universe. It is therefore very unlikely, but not impossible that one of the GWs was strongly-lensed. We identify three spectroscopically confirmed cluster strong lenses within the 90% credible sky localisations of the three GWs. Moreover, the GW credible regions intersect the disk of the Milky Way, behind which undiscovered strong galaxy cluster lenses may reside. We therefore use well constrained mass models of the three clusters within the credible regions and three further example clusters to predict that half of the putative next appearances of the GWs would be detectable by LIGO, and that they would arrive at Earth within three years of first detection.

Bibliographic note

5 pages, 2 figures, submitted to MNRAS Letters


Original languageEnglish
Pages (from-to)3823-3828
Number of pages6
JournalRoyal Astronomical Society. Monthly Notices
Issue number3
Early online date11 Jan 2018
Publication statusPublished - Apr 2018


  • astro-ph.HE, astro-ph.CO, astro-ph.GA