Digital array scanned interferometers for astronomy

We report investigations of digital array scanned interferometers (DASI) with silicon CCD array detectors to define the operational capabilities of a mapping (polarimetric) spectrometer for astronomical applications based on these instruments. For spectral mapping, we demonstrate spatially resolved spectra using a cylindrical lens to image in the interferometer's redundant coordinate. We demonstrate enhanced spectral resolution with a band limiting filter and standard aliasing techniques. The signal-to-noise characteristics of the Fourier transformed data are demonstrated with regard to the effects of a rectangular sampling function, spectral multiplexing and the pixel-to-pixel variation of the CCD array.These data indicate that DASIs can offer simple, versatile (polarization) mapping spectrometers suitable for spectral mapping observations from the ultraviolet to the infrared of extended sources at variable spatial resolution, particularly where long term stable operation is essential, as for spaceraft instruments.This research was supported by NASA under grants NAGW-122 and NAGW-1801.