Plasma chemistry of sprite streamers

Formation of sprite streamers at subbreakdown conditions from ionospheric inhomogeneities resembling observed sprite halo structures

[1] Modeling results of sprite streamer formation from large ionospheric inhomogeneities or patches (several tens to hundreds of meter wide) indicate that positive streamers can be initiated at subbreakdown conditions from the inhomogeneities with a density comparable to sprite halo densities. For spherical patches with a given radius, the minimum density required for streamer initiation decrea...

Chemistry of sprite discharges through ion-neutral reactions

Emergence of sprite streamers from screening-ionization waves in the lower ionosphere

Sprite discharges above thunderclouds at altitudes of 40–90 km (refs 1–5) are usually created by a strong positive cloud-to-ground lightning flash6. Sometimes these sprite discharges emerge from a visible halo5,7–9, and during the first stage they always propagate downwards and branch on their way5,7,9–11. Modelling efforts have been restricted to conditions of non-ionized air of constant densi...

Molecular nitrogen LBH band system far-UV emissions of sprite streamers

[1] The time dependent optical emission model developed by Liu and Pasko (2004) is applied to studies of far-UV emissions of sprite streamers due to N2 Lyman-BirgeHopfield (LBH) band system. Modeling results indicate that the LBH emissions of sprite streamers at 70 km are generally stronger by up to a factor of 10 than those from the first negative band system of N2 , and experimental measureme...

Luminosity and propagation characteristics of sprite streamers initiated from small ionospheric disturbances at subbreakdown conditions

[1] This paper reports a modeling study on sprite streamer formation at subbreakdown conditions, i.e., the initiation of sprite streamers in a lightning field below the breakdown threshold field Ek. Successful formation of streamers is observed for a variety of electric fields with the lowest field of 0.3Ek when an appropriate ionization column is introduced. The simulation results also indicat...