J Phys D Appl Phys 28:331–337Īramyan A, Galechyan GA, Harutyunyan GG (2008) Superluminescence of atomic oxygen in the upper atmosphere. Īllen NL, Ghaffar A (1995) The conditions required for propagation of cathode-directed positive streamer in air. In the remainder of this paper, we focus our attention on the properties of UV flashes in the mesosphere, which have been observed onboard Russian microsatellites “Universitetsky-Tanyana” and “Vernov.” Such a kind of optical flash is referred to as a transient atmospheric event, which differs from the TLEs in optical energy, duration and other parameters.Īdachi T, Sato M, Ushio T, Yamazaki A, Suzuki M, Kikuchi M, Takahashi Y, Inan US, Linscott I, Hobara Y, Frey HU, Mende SB, Chen AB, Hsu R-R, Kusunoki K (2016) Identifying the occurrence of lightning and transient luminous events by nadir spectrophotometric observation. In this paper, we review a few analytical results, which have been recently derived from simple physical models of the TLEs phenomena. Because of this, the majority of theoretical study of TLEs and other large-scale optical phenomena at high altitude are based on numerical modeling of the basic kinetic, transport and electrodynamic equations describing TLEs evolution, whereas the analytical theory remains a formidable task to be accomplished. A set of electrodynamic and transport kinetic equations describing the TLEs are complicated because the number densities, mobilities of electrons and ions, reaction constants and other parameters are strongly dependent on altitude. Considerable study has been given to ULF/ELF measurements which can provide us with important information on the delayed sprite generation and the role played by IC processes in the perturbation of the lower ionosphere above the sprite. The sprite initiation, visible evolution, streamer structure, and their relationship with intra-cloud (IC) process are discussed. In this paper, we review various types of TLEs, including recently discovered dancing sprites, gnomes, ultraviolet (UV) atmospheric flashes and other effects. This progress is caused by several factors including satellite optical observations, ground-based measurements of sprite-produced electromagnetic fields, the use of high-speed video observations and telescopic cameras with high resolution that enables one to trace the dynamics of sprite and BJ development. Transient luminous events (TLEs) such as sprites, blue jets (BJs) and elves have been studied intensively during the last three decades, and much is now known of their properties.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |