Matched-filter study and energy budget suggest no detectable gravitational-wave ‘extended emission’ from GW170817

Paper published by Miquel Oliver, David Keitel, Andrew L. Miller, Hector Estelles, Alicia M. Sintes at the Monthly Notices of the Royal Astronomical Society.

Matched-filter study and energy budget suggest no detectable gravitational-wave ‘extended emission’ from GW170817

van Putten and Della Valle (2018) have reported a possible detection of gravitational-wave ‘extended emission’ from a neutron star remnant of GW170817. Starting from the time–frequency evolution and total emitted energy of their reported candidate, we show that such an emission is not compatible with the current understanding of neutron stars. We explore the additional required physical assumptions to make a full waveform model, for example, taking the optimistic emission from a spinning-down neutron star with fixed quadrupolar deformation, and study whether even an ideal single-template matched-filter analysis could detect an ideal, fully phase-coherent signal. We find that even in the most optimistic case an increase in energy and extreme parameters would be required for a confident detection with LIGO sensitivity as of 2018-08-17. The argument also holds for other waveform models following a similar time–frequency track and overall energy budget. Single-template matched filtering on the LIGO data around GW170817, and on data with added simulated signals, verifies the expected sensitivity scaling and the overall statistical expectation.

Image.Single-trial detection and false-alarm probabilities for the single-detector matched-filter SNR.

Paper link available below at citation information

Citation:
Miquel Oliver, David Keitel, Andrew L. Miller, Hector Estelles, Alicia M. Sintes
Matched-filter study and energy budget suggest no detectable gravitational-wave ‘extended emission’ from GW170817
Monthly Notices of the Royal Astronomical Society, Volume 485, Issue 1, May 2019, Pages 843–850
DOI: https://doi.org/10.1093/mnras/stz439
15 February 2019