vyp Year Power (Amplitude) Spectrum
The power spectra is produced with a non-power-of-2 FFT from the time series.
Dimensionally, frequency is along the x-axis, the y-axis contains the order of the spherical harmonic, M, from -L to +L, and the z-axis contains the power [*,*,1]. The FITS header keyword, CD1_1, gives the conversion factor (microHz/pixels) for the x-axis.
Data products up to mrvyp951226 include the power and phase and have an L range of (0<=L<=30). Products after that date do not include the phase and have an L range of (0<=L<=45).
Steps involved: 1. Calculate the power spectra of a GONG time series image with pseries. lpar pseries input = "@ts" List of input Time-Series images output = "@ps" List of output Power-spectrum images (type_output = "gong") Output data type (fft|power|gong) (pad = "none") Zero padding (none|1st|2nd) (debias = yes) Debias time series prior to FFT (use_gapfill = yes) Used gap-filled data? (do_phase = no) Output phase spectra (window = "none") Window (bartlett|hamming|hanning|parzen|welch|n (verbose = yes) Verbose output (mode = "a") output mrvypYYMMDDd[000-045] sample FITS header output GHIST018= 'Task PSERIES2 (96/06/25 17:58:45, V93.2.31)' GHIST019= 'input=/int01/chavez/Year/Year/mrvyt951208ed045.imh,type_output=g' GHIST020= 'ong,window=none,use_gapfill=yes' 2. Write the power spectra to a DSDS tape. tape1 (0<=L<=45) 2.34Gbytes (for one entire GONG year)
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