ISUAL multi-band observations of elves

The Imager of Sprites and Upper Atmospheric Lightning (ISUAL) experiment on the FORMOSAT-2 satellite inferred the global occurrence rates of sprites, halos and elves to be ~1, ~1 and 35 events/min, respectively [1, 2]. Hence, elve is the most abundant type of transient luminous events (TLEs). From analyzing brightness observed by ISUAL Imager through different filters (1PN
₂
, 762, 630, 557.7, 427.8 nm), the relative intensity of the OH (9,3), O
¹
D, O
¹
S, 1NN
₂
⁺
and O
₂
Atmosphere band (0,0) emissions in elves will be discussed.