Targeted Sub-threshold Search for Strongly-lensed Gravitational-wave Events

Understand

Strong gravitational lensing of gravitational waves can produce duplicate signals separated in time with different amplitudes.

• We consider the case in which strong lensing produces superthreshold gravitational-wave events and weaker subthreshold signals buried in the noise background.
• We present the GstLAL-based TargetEd Subthreshold Lensing seArch search method for the subthreshold signals using reduced template banks targeting specific confirmed gravitational-wave events.
• We perform a simulation campaign to assess the performance of the proposed search method.