Cross-correlation method for intermediate-duration gravitational wave searches associated with gamma-ray bursts

Abstract

Several models of gamma-ray burst progenitors suggest that the gamma-ray event may be followed by gravitational wave signals of 10 3 -10 4 seconds duration (possibly accompanying the so-called X-ray afterglow "plateaus"). We term these signals "intermediate-duration" because they are shorter than continuous wave signals but longer than signals traditionally considered as gravitational wave bursts, and are difficult to detect with most burst and continuous wave methods. The cross-correlation technique proposed by [S. Dhurandhar et al., Phys. Rev. D 77, 082001 (2008)], which so far has been used only on continuous wave signals, in principle unifies both burst and continuous wave (as well as matched filtering and stochastic background) methods, reducing them to different choices of which data to correlate on which time scales. Here we perform the first tuning of this cross-correlation technique to intermediate-duration signals. We derive theoretical estimates of sensitivity in Gaussian noise in different limits of the cross-correlation formalism, and compare them to the performance of a prototype search code on simulated Gaussian-noise data. We estimate that the code is likely able to detect some classes of intermediate-duration signals (such as the ones described in [A. Corsi & P. Mészáros, Astrophys. J., 702, 1171(2009]) from sources located at astrophysically-relevant distances of several tens of Mpc.

Search for Post-merger Gravitational Waves from the Remnant of the Binary Neutron Star Merger GW170817

“…However, sensitivity can be improved by targeting specific emission models (e.g., Coyne et al 2016).…”

Observationally constraining gravitational wave emission from short gamma-ray burst remnants

“…In reality, alternative algorithms are used that require the strain be increased by a factor of a few (equivalently, the distance must be reduced by a factor of a few) for the pipelines to make a detection with equivalent false alarm and false dismissal rates as seen with the optimal matched filter (e.g., Thrane & Coughlin 2013;Thrane & Coughlin 2015;Coyne et al 2015). In the spirit of deriving strict upper limits on the signal-to-noise ratio, we persist with equation (20) for the remainder of this article, but note that realistic detection algorithms will reduce the signal-to-noise ratio by some non-negligible factor.…”

Cross-correlation search for continuous gravitational waves from a compact object in SNR 1987A in LIGO Science run 5

“…As foreshadowed in Section IV A and IV B, we do not discuss the non-Gaussian corrections caused by dependent pairs in this paper, because they are negligible for T obs = 1 yr; for more details see Ref. [69]. Hence the threshold reduces to…”

“…T obs = 1 hr, 5 hr in our test), the skewness and kurtosis deviate significantly from the expected values in a Gaussian distribution, and hence the correction to ρ discussed in Ref. [69] is required. However, in a long-duration search with T obs = 1 yr, the above moments of ρ match those of a Gaussian distribution to an accuracy above 95%, so the correction is negligible for the search in this paper.…”

“…As a result, the ρ α values are not statistically independent. Coyne et al [69] discussed the correction to ρ for dependent ρ α , finding that ρ is distributed as a χ 2 distribution with two degrees of freedom instead of a Gaussian distribution (for more details, see [69]). This correction is crucial to an intermediate-duration search (T obs 10 4 s).…”