Open AccessEvidence for the resonator of inertial Alfvén waves in the cusp topside ionosphere
Author(s) -
Hirano Yumi,
Fukunishi Hiroshi,
Kataoka Ryuho,
Hasunuma Tomoyuki,
Nagatsuma Tsutomu,
Miyake Wataru,
Matsuoka Ayako
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 - 10.1029/2003ja010329
Subject(s) - physics , ionosphere , geophysics , alfvén wave , amplitude , electric field , cusp (singularity) , computational physics , magnetic field , altitude (triangle) , magnetohydrodynamics , optics , geometry , mathematics , quantum mechanics
Using Akebono satellite observations, we have examined the excitation mechanism of large‐amplitude, electric and magnetic field variations in the vicinity of the cusp topside ionosphere. Three typical cusp events in the altitude range of ∼2000 km, ∼4000 km, and ∼7500 km are investigated in detail. The phase‐frequency relationship obtained from a wavelet analysis is compared with the theoretical one given by the Lysak 1991 model for each event to find the evidence for the existence of ionospheric Alfvén resonator (IAR). Also, the ratios of electric field to magnetic field variations are compared with theoretical values of inertial Alfvén waves to identify the existence of inertial Alfvén waves. The obtained results demonstrate the clear signature of the coexistence of IAR and inertial Alfvén waves in extended altitude range of the cusp topside ionosphere.