The first LIGO-Virgo search for gravitational-wave lensing

LIGO/Virgo researchers have performed the collaboration’s first search for gravitational lensing signatures using the gravitational-wave observations from the first half of LIGO-Virgo’s third observing run. David Keitel, Beatriz Galindo Distinguished Researcher in the GRAVITY group and the IAC3 at UIB, was an editorial team member and one of the two project managers for this work.

The paper, now available on the arXiv, studies how the gravity of massive objects – acting like a giant “lens” – could possibly change the paths and properties of gravitational waves. While no compelling evidence for lensing was found, the paper discusses statistical forecasts of lensed event rates and places constraints on the binary black hole merger rate. It considers the way lensing could magnify gravitational-wave signals (and possibly contribute to observed high-mass events), produce candidates for multiple images (created by the waves taking separate paths around a lens), and the possible effects of smaller “microlenses” on the observed signals.

See the paper’s science summary for more details.