A digital filter for removing known components from spectroscopic data

This document presents a computational system designed to remove known components from spectroscopic data. The system realization is a FORTRAN-7 7 program; a listing of the program's source code is included in the Appendix.

The program first performs a nine-point quadratic least-squares smoothing function. It then removes the known component with a non-recursive filter based on a least-squares prediction of the observed spectrum and a least-squares prediction of a computer generated synthetic spectrum of the known component.

The program was tested using an artificial spectrum created for the sole purpose of testing the program's function.

The program's function was verified with three segments of the 12 micron band of ethane taken from data recorded on the Fourier transform spectrometer at the McMath solar telescope at the Kitt Peak National Observatory. The segments are located near 804.0, 815.0, and 819.5 cm^-1. Plots of the spectral data and of the resultant data are included.