Waveform models for the gravitational-wave memory effect: II. Time-domain and frequency-domain models for nonspinning binaries

Understand

The nonlinear gravitational-wave (GW) memory effect$\unicode{x2014}$a permanent shift in the GW strain that arises from nonlinear GW interactions in the wave zone$\unicode{x2014}$is a prediction of general relativity which has not yet been observed.

• The amplitude of the GW memory effect from binary-black-hole (BBH) mergers is small compared to that of primary (oscillatory) GWs and is unlikely to be detected by current ground-based detectors.
• Evidence for its presence in the population of all the BBH mergers is more likely, once thousands of detections are made by these detectors.
• Having an accurate and computationally efficient waveform model of the memory signal will assist detecting the memory effect with current data-analysis pipelines.