Main Points:
- The analysis is for 2 events only, both large sprites (jellyfish)
- Generally green ghosts are relatively rare
- Altitude around 90-95 km; same altitude as the auroral green line
(atomic oxygen)
- Ghost reaches peak intensity 50-120 ms after the sprite turn-off
- The observed exponential decay has a time constant 0.6 – 0.25 s; this
is less than the 0.7 s value for the 557.7 nm atomic oxygen emission
in vacuum, but higher than 0.2-0.1 s expected based on data in
Vallance Jones (1974)
- The last two bullets suggest additional processes beyond the duration
of the main sprite