vyw Year Power Spectrum of Window Function
This step calculates the power spectrum of the observation window of a GONG time series for each L-value which are stacked together to form the final output.
Dimensionally, the x-axis is frequency from -20 to 20 microHz and the y-axis is spherical harmonic degree, L, with the value of the sample as the normalized power.
Steps involved: 1. Produce the power spectrum of the window function with pwindow. lpar pwindow input = Input window time series image output = "pswin20" Output normalized window power spectrum image (range = 20) Output frequency range about central peak (microHz) (fft = no) Output complex FFT rather than Power/Phase (type_fft = "nonpwr2") Type of FFT (pwr2 | nonpwr2) (use_gapfill = yes) Used gap-filled data (for GONG format only)? sample FITS header output GHIST000= 'Task PWINDOW (96/06/21 11:50:44, V93.2.31)' GHIST001= 'input=mrvyt951226d000,range=20.,fft=no, type_fft=nonpwr2' 2. Further reductions. imcopy("pswin20*.imh[*,1,1]","pswin20*.imh") imstack("pswin20*.imh","mrvywYYMMDD") output mrvywYYMMDD
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