Observations of the Zeta Spectrum in the Wave-length Range 16 Å–400 Å

Abstract

SPECTROSCOPIC studies of Zeta¹ are now being carried out in the important wave-length region below 400 Å. Previous investigations in the vacuum ultra-violet have been mainly confined to the region between 400 Å and 2000 Å using a variety of vacuum grating spectrometers with both photographic and photoelectric detectors. Thus, spectral line identifications have been made by Butt et al.¹, and Fawcett et al.². Measurement and interpretation of the temporal variation of spectral line intensities have been made by Burton and Wilson³, and Hobbs et al.⁴, and measurement of the Doppler profiles of spectral lines has been made by Jones and Wilson⁵. More recently, observations have been made by Heroux^6,7, who measured the relative intensities of spectral lines in order to determine the electron temperature, using a grazing incidence rocket monochromator⁸.