Open AccessA possible generation mechanism of temporal and spatial structures of flickering aurora
Author(s) -
Sakanoi K.,
Fukunishi H.,
Kasahara Y.
Publication year - 2005
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2004ja010549
Subject(s) - physics , flicker , ionosphere , electron precipitation , photometer , optics , flux (metallurgy) , geophysics , magnetosphere , magnetic field , quantum mechanics , electrical engineering , engineering , materials science , metallurgy
Optical observations of flickering aurora by a high‐speed imaging photometer system were carried out at Syowa Station in 1998. A comparison between observed parameters of flickering aurora and theoretical values of dispersive Alfvén waves indicates that observed flickering aurora would be produced by electron flux modulations by electromagnetic ion cyclotron waves or inertial Alfvén waves in the auroral acceleration region located over the altitude range of ∼2000–5000 km. Interference wave patterns of two dispersive Alfvén waves in a resonance cone can explain the observed temporal and spatial structures of flickering aurora; flickering columns (or spots) remain in almost the same location during their lifetime and that their shapes become indistinguishable every half flickering period at the timing of the interchange of the bright and dark columns (or spots).