Calibration and Reconstruction in Time-Series of Strain Signal of Gravitational Wave Detector

In operation of laser interferometric gravitational wave detectors, we have to reconstruct the strain signal of space-time metric from an output of electric signal of interferometer servo. In many past works, the strain signal reconstructions have done in frequency domain using Fast Fourier Transform with finite time slices using calibrated transfer function. However optimal length of time slices is different according to methods of gravitational wave searches, e.g. matched filtering, excess peak, etc. Thus we need re-generate calibrated data for all variations of data analysis in this method. Also for more general-purpose data for analysis or for any other evaluation, we develop reconstruction method of strain-calibrated data using time series filter. We will show an analytical framework of the time series filter for the calibration and will demonstrate the numerical processing using CLIO observational data. We apply this process using FIR filter and obtain result that residual error between our new method and previous one is about 20%. The calibration error in the compact binary coalescence is estimated as ∼8% large average and ∼24% fluctuation in a comparison with ideal waveform.