THE EXCITATION OF THE TRIPLET LINES OF O-2+ IN NEBULAE

The excitation of the triplet lines of 02+ between 280 and 380 nm in nebulae is attributed to a combination of the Bo wen fluorescence mechanism pumped by the He+ resonance line and charge transfer into excited states of 02+ in collisions of 03+ with neutral hydrogen atoms. The lines at 377.4 and 375.7nm are due almost entirely to charge transfer population of the (2p 3p)3DX level. The close agreement obtained between the calculated and observed line intensities confirms the accuracy of the charge transfer rate coefficients. © Royal Astronomical Society.