Speaker
Description
I'll present a method to optimize the analysis of long-duration Gravitational Waves (GWs) from compact binary coalescences (CBCs). A typical example is GWs from compact objects with masses below that of the Sun. The LIGO–Virgo–KAGRA (LVK) collaboration, operating the world’s most sensitive GW observatories, searches for CBC signals in the 0.2–1.0 solar mass range, providing leading constraints on the abundance of Primordial Black Holes (PBHs).
For such long-duration signals, sensitivity is limited by the computational cost of dense template banks and the memory requirements of the analysis. Current searches mitigate these challenges by increasing a low-frequency cutoff (e.g., 45 Hz), which reduces computational demands but sacrifices sensitivity. Our study indicates that incorporating lower-frequency data could improve PBH abundance limits by up to ~36%. Moreover, next-generation GW detectors will achieve greater sensitivity at low frequencies, inevitably increasing signal durations.
To address these challenges, we propose a method that applies a heterodyne-like technique, enabling efficient exploration of long-duration waveforms. For a given target waveform, we generate a ratio with respect to a reference waveform. The resulting “ratio waveform” has a duration approximately equal to the difference between the two original durations, making it much more compact. This allows matched filtering to be performed on a shorter waveform while preserving the full sensitivity of the original signal.
This approach substantially reduces both computational cost and memory usage, enabling the analysis of signals that would otherwise be prohibitive to search. Our method is directly applicable to current detectors and will be increasingly valuable for the low-frequency sensitivity of future GW observatories.
