Heavner, M. J., Morrill, J. S., Siefring, C., Sentman, D. D., Moudry, D. R., Wescott, E. M., & Bucsela, E. J. (2010). Near‐ultraviolet and blue spectral observations of sprites in the 320–460 nm region: N2 (2PG) emissions. Journal of Geophysical Research: Space Physics, 115(A7).
Abstract
A near-ultraviolet (NUV) spectrograph (320–460 nm) was flown on the EXL98 aircraft sprite observation campaign during July 1998. In this wavelength range video rate (60 fields/sec) spectrographic observations found the NUV and blue emissions to be predominantly N2 (2PG). The negligible level of N2+ (1NG) present in the spectrum is confirmed by observations of a co-aligned, narrowly filtered 427.8 nm imager and is in agreement with previous ground-based filtered photometer observations. The synthetic spectral fit to the observations indicates a characteristic energy of ∼1.8 eV, in agreement with our other NUV observations.