Experimentally determined oscillator strengths and linewidths for the Schumann-Runge band system of molecular oxygen—III. The (7-0) to (19-0) bands

Abstract

Experimental oscillator strengths and predissociation linewidths have been derived from equivalent width measurements at room temperature for the (11-0) to (15-0) Schumann-Runge bands of molecular oxygen, and at low temperature for the (15-0) to (19-0) bands, using the Adelaide 6 m vacuum ultraviolet monochromator operated at a resolution of 0.006 nm. Photometric methods were used to measure the ultraviolet absorption for 40 groups of ratational lines, and the resulting data were interpreted using a curve of growth type of analysis to give oscillator strengths and pre-dissociation linewidths. The variation of the oscillator strengths with N‴ within each band was found to agree well with the theoretical predictions of Allison, while the mean band oscillator strengths derived from the results are in good agreement with previous measurements. The results demonstrate the need for accurate data about multiplet line splittings. A revised analysis of previous data for the (7-0) to (14-0) bands is also presented.