Generation of Nitrogen Emission Line at 337 nm in the Laboratory and at High Altitudes

Nitrogen Laser Emissions of Short and Long Durations Generated in Air

“…This implies that ahead of the detonation front, we have the breakdown wave, i.e., a pure phase velocity without mass motion (hence, no Doppler effect). The net result of having the absorption length means that the energy content of the sprites observed has the smaller value of the energy, in comparison to the energy needed when the absorption length is short as it was done in [6].…”

“…These facts have the bearing on the generation of N 2 laser emission and the creation of sprites and elves [6]. The size of the sprite was estimated initially using the Chapman-Jouguet condition for the detonations [18], [19]…”

“…The purpose of conducting this research and development is also to get the background information that is required to help design the explosively driven magnetocumulative generator (MCG), capable of producing the train of N 2 laser pulses, necessary for high-altitude studies of sprites in order to help us understand better the origin of the Tunguska event [6]. By introducing the concave mirror, it was demonstrated that the current experimental setup is capable of producing the laser spark, i.e., the laser-induced electrical breakdown in atmospheric air.…”

“…To explore further the importance of impedance, an eightstage, pulse-forming network (PFN) Marx generator with 50-internal impedance was used in [6]. The pulses of nitrogen emission at 337.1 nm of long duration (<3 μs) and of short duration (∼10 ns) were obtained.…”