Open AccessPc5 field line resonance frequencies and structure observed by SuperDARN and CANOPUS
Author(s) -
Ziesolleck C. W. S.,
Fenrich F. R.,
Samson J. C.,
McDiarmid D. R.
Publication year - 1998
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 - 10.1029/98ja00590
Subject(s) - magnetometer , radar , ionosphere , physics , resonance (particle physics) , computational physics , geophysics , wavenumber , magnetic field , geology , geodesy , nuclear magnetic resonance , remote sensing , optics , atomic physics , computer science , telecommunications , quantum mechanics
We have analyzed a number of low‐m Pc5 field line resonance events observed simultaneously by one or more of the Super Dual Auroral Radar Network (SuperDARN) radars and the Canadian Auroral Network for the OPEN Unified Study (CANOPUS) magnetometer array. At times there was excellent agreement in the Pc5 signal frequencies observed by radar and magnetometers. For events with good agreement in the measured signal frequencies, there was also reasonable agreement in the observed resonance positions and m numbers. Sometimes, however, the ordering of frequencies by their spectral power did not coincide between the radar and magnetometer data and even the frequencies of the spectral peaks did not always coincide. In these cases, there was also some apparent discrepancy in the observed resonance positions and m numbers. The resonance half power widths observed by the magnetometers were found to be a factor of 2 – 6 wider than those measured with the radar, owing to the spatial integration by ground‐based magnetometers of ionospheric current structures having scale size less than ionospheric height. Although there was general agreement in the direction of the longitudinal propagation, the m numbers obtained from the magnetometer data were found to be somewhat smaller that those calculated from the radar data. We consider and discuss possible reasons for the observed discrepancies.