A comprehensive re-analysis of the O2 (B3Ʃ–u – X 3Ʃ–g) Schumann-Runge band system

The emission spectrum of O2 has been excited, recorded and measured between 2116 and 5663 Å. Of the 7700 emission lines which were measured, 5400 have been assigned to 87 bands of the B3Ʃ–u — X3Ʃ–g Schumann-Runge system of O2. Many of these are reported for the first time. A computer-based Loomis-Wood method has been used to assign all of these measurements to unambiguous transitions from which a self-consistent set of molecular constants has been derived. Molecular constants for the b1Ʃ+g – X3Ʃ–g atmospheric red system of O2 have been recalculated. A critical assessment has been made of the molecular constants derived from all previous analyses of the Schumann-Runge system.