Reduction of SOLIS/Vector Spectromagnetograph He I 1083 nm Observations


The SOLIS/Vector Spectromagnetograph (VSM) now continues the three- decade record of full-disk He I 1083 nm spectroheliograms from NSO/Kitt Peak (see poster by Henney et al.). Although the sensitivity of the VSM interim cameras at 1083 nm is far greater than that of previous NSO/KP instruments, the observations are compromised by strong interference fringes produced within the detectors. We discuss in some detail the extent to which this difficulty is overcome in the simple algorithm used to produce the synoptic observations and explore methods for removing remaining fringe effects for true imaging spectroscopy. These techniques include Fourier and Wavelet filtering, the flat- fielding algorithm used for earlier NASA/NSO Spectromagnetograph (SPM) observations, and physical modeling of the detector fringe pattern.

AGU Spring Meeting Abstracts