METASTABLE HE-1083 NM INTENSITIES IN THE TWILIGHT - A RECONSIDERATION

The 1083 nm airglow emission arising from the resonant scattering of solar photons by metastable He(2(3)S) atoms is potentially valuable for remote sensing of total photoelectron fluxes and neutral helium densities at altitudes above the F2 peak. In this study, we adopt the diffusion picture used in all previous studies and point out that even within this crude approach, intensities consistent with the winter observations (greater than or similar to 1000 R) collected in Tinsley and Christensen [J. Geophys. Res., 81, 1253, 19761 are obtained when the correct parameter values for He(2(3)S) production, loss, and transport are applied and line-of-sight geometries are properly taken into account.