Altitude Resolved Sprite Spectra

A large aperture imaging spectrograph was used to obtain sprite spectra during an observational campaign at Langmuir Laboratory, Socorro, New Mexico, in June and July 2005. The spectrograph slit was orientated vertically. Hence the spatial dimension along the slit would represent altitude within the sprite imaged on the slit. The spectra were recorded on a digital intensified CCD capable of 1000 frames per second, i.e. millisecond time resolution, but most spectra were recorded using a frame rate of 300 per second. The images cover a wavelength range of about 170 nm within the spectrograph's range from 450 nm to 900 nm. The spectral resolution is ~2 nm. Examples of height resolved spectra will be presented. The spectra are dominated by molecular nitrogen emissions. Synthetic molecular nitrogen spectra including the 1PG and Meinel bands fit the observed spectra well.