[BUNDLES\]SPECTRAL_CLEAN FFT
Clean the Fourier Transform along the spectral axis of the DIRTY cube,
and transform back the Clean components to retrieve the per-channel
Clean components. The final Clean image is produced using UV_RESTORE.
The usual Clean convergence parameters apply, although CLEAN_NKEEP may
need small adjustment because of the non-positive nature of the signal.
The Fourier Transform leads to a Complex valued data set, whose Her-
miticity is not considered. Real and Imaginary parts are cleaned sepa-
rately, so the method is about twice slower than a standard Clean.
Gildas manager
2023-06-01