A smooth band cut suppresses removed-interval leakage after GW170817 in three tested bands

We measure filter leakage in public GW170817-v3 strain. A half-second interval around the known Livingston glitch is removed before three band filters are applied. In the 100 to 300 Hz band, its response has a maximum local RMS of 3e-23 strain from 0.05 to 2 seconds after merger with a sharp Fourier cut. A 20 Hz cosine taper reduces this response by a factor of 2727. Two other bands retain strong suppression. A filter with a 0.25-second response on each side has no overlap. None of the Livingston pulse scores is unusual at a 1 percent rank against 464 identically processed controls. Gate-width checks, a Hanford follow-up and a direct convolution audit define the scope. The removed interval also contains inspiral signal and noise. It is not a pure glitch model. This is a data-specific method check, not a new source or a test of published source parameters. Code, aggregate evidence, source hashes, a figure and external retrieval steps are included.

astronomy · GW170817 · filter leakage · instrumental glitch · finite support · noise controls