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...his data was derived from published site location/orientation information and detector noise power spectra design goals [26], using the stochastic background data analysis routines contained in GRASP =-=[27]-=-. (See Sec. VII for more information about the computer code that we wrote to perform these calculations.) 58A. Noise power spectra Figures 10-13 show the predicted noise power spectra for the initia...

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... the mode “signal” and other contributions to the measured detector output: i.e., it detects the violin modes. This distinguishes it from other methods (e.g., multitaper methods, linear notch filters =-=[8]-=-) which purport to characterize or remove artifacts, but which in fact simply suppress all contributions to the noise within a narrow band, not distinguishing violin mode from other contributions. The...

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...s. In particular, for binary inspiral searches a χ2 time–frequency discriminator is used as a veto for the output of matched filter, by analyzing the output of different frequency bands. This χ2 test =-=[22, 23]-=- was specifically constructed for broadband signals, but it can be modified for signals that are narrowband as the continuous wave signals expected from rapidly rotating neutron stars. For these conti...

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... dimensionless factor included to account for the different values of H0 quoted in the literature [3]. The above correlations are satisfied if the GW strains at each interferometer are represented by =-=[4]-=- ˜h1(f ) = √ 3H 20 T 40π2 |f |−3/21/2(|f |)(x1(f ) + iy1(f )), (3) Search for a stochastic background in LIGO S679 ˜h2(f ) = ˜h1(f )γ (|f |) + √ 3H 20 T 40π2 |f |−3/21/2(|f |) √ 1 − γ 2(|f |)(x2(f )...

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...0/0 ◦c2000 Plenum Publishing Corporation 386 Allen and Ottewill We have implemented multi-taper methods as part of the grasp (Gravitational Radiation Analysis and Simulation Package) software package =-=[1]-=-. These programs may be used to address issues relating to gravitational wave detection, both for detector characterisation, for example: • The characterisation of power line harmonics, and specific s...

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...h of the distribution of these frequencies is ∼ 100 Hz. Assuming that the ‘chirrup’ is very steep near the coalescence and that the frequency of emission is within ∼ 500 Hz of ¯ν for ≪ 1 s (see, eg., =-=Allen 1997-=-) , we may assume, as we ultimately wish to co-add signals at the detector, that the spectral profile at the source for NS–NS coalescence has a width of σ ∼ 500 Hz. The issue of the actual value of ¯ν...

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..., to yield a manageable number of triggers. 3. The standard χ 2 test The technique of calculating a χ2 to check the consistency of a trigger with the expected waveform was developed several years ago =-=[7]-=- and has been utilized in published inspiral searches [8, 9, 5]. The inspiral template is effectively divided into p sub-templates labeled by l = {1, 2, ..., p}, each of which contains a different fre...

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...arching a transient signal of unknown form it is very important to have a whitened noise [12, 13]. The importance of whitening data is also linked to the possibility of reducing their dynamical range =-=[37, 36]-=-. The aim of this paper is to show how to identify the noise PSD and how to whiten the data produced by an interferometric detector before applying any algorithm detection. In the section 2 we underli...