vdt: Site Dependent Day Complex SHT Time Series
vdp: Site Dependent Day m-nu Power Spectrum
vdl: Site Dependent Day l-nu Diagram Image (Power Spectrum)

DNSPIPE creates the site day mode coefficient time series, power spectra and l-nu diagrams from calibrated velocity images (the vzi files output from VMBICAL.) The images are registered in heliographic coordinates, temporally detrended using a 2-point backward difference filter, then run through a spherical harmonic transform to generate the time series images from L=0 to L=200. The y axis of the time series images represents the m value (M=0 to M=L) with the imaginary part of the SHT (M=L to M=-L) in the third pixel dimension (*vdt*[*,*,2].) There are two window functions, each in the L+2 row of both the real and imaginary parts of the time series. The [*,L+2,1] is the observed window function, and the [*,L+2,2] represents the window after gapfilling. The x axis represents time in minutes. TS_START and TS_END correspond to the date/time of the first and last pixel column in the time series.

Before the time series is gapfilled, TSCLEAN is called to remove anomalous time samples in the L=0 to L=19 images. This will alter the observed window when abnormally high data points are found. PSERIES is called to generate the power spectra from the gapfilled time series (no longer archived.) The site day l-nu diagrams are produced from the power spectra and are available online.

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