Knowledge Bank

The Atmospheric Band System of $O2$ has been extensively studied over many years. However, very few vibrational levels of the upper state are known. Some of the best data still come from Babcock and Herzberg’s solar absorption study, published in $1984a$, for which the highest vibrational level is $v\prime =3$. In emission, vibrational levels up to $v\prime =5$ have been observed in aurora, but rotationally-resolved spectra from the atmosphere have been limited to $v\prime =0$, and specifically to the 0-1 band. New observations made with the Keck telescope and the HIRES echelle spectrograph ($0.34cm-1$ spectral resolution) on Mauna Kea show a wealth of nightglow emission data for the $O2(b-X)$ transition, emanating from O-atom recombination at 90-100 km $altitudeb,c$. We have analyzed these rotationally-resolved bands extending to $v\prime =7(\Delta v\prime =0,1)$ and expect to find bands from yet higher levels. Isotopic emissions in the 0-0 band at 762 nm are also observed.