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تسجيل مستخدم جديدReducing the effect of seismic noise in LIGO searches by targeted veto generation
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The Laser Interferometer Gravitational-Wave Observatory forms part of the international effort to detect and study gravitational waves of astrophysical origin. One of the major obstacles for this project with the first generation detectors was the effect of seismic noise on instrument sensitivity - environmental disturbances causing motion of the interferometer optics, coupling as noise in the gravitational wave data output. Typically transient noise events have been identified by finding coincidence between noise in an auxiliary data signal (with negligible sensitivity to gravitational waves) and noise in the gravitational wave data, but attempts to include seismometer readings in this scheme have proven ineffective. We present a new method of generating a list of times of high seismic noise by tuning a gravitational wave burst detection pipeline to the low frequency signature of these events. This method has proven very effective at removing transients of seismic origin from the gravitational wave (GW) data with only a small loss of analysable time. We also present an outline for extending this method to other noise sources.
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