Electron acceleration observed by the FAST satellite within the IAR during a 3 Hz modulated EISCAT heater experiment

A quantitative analysis is presented of the FAST satellite electric field and particle flux data during an EISCAT heating experiment run on 8 October 1998. Radio frequency heating, modulated at 3 Hz, launched ULF waves from the ionosphere into the lower magnetosphere. The ULF waves were observed in...

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Bibliographic Details
Published in:Annales Geophysicae
Main Authors: S. R. Cash, J. A. Davies, E. Kolesnikova, T. R. Robinson, D. M. Wright, T. K. Yeoman, R. J. Strangeway
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2002
Subjects:
Q
Online Access:https://doi.org/10.5194/angeo-20-1499-2002
https://doaj.org/article/cfb2975a79974242a716214aaa18f8b0
Description
Summary:A quantitative analysis is presented of the FAST satellite electric field and particle flux data during an EISCAT heating experiment run on 8 October 1998. Radio frequency heating, modulated at 3 Hz, launched ULF waves from the ionosphere into the lower magnetosphere. The ULF waves were observed in FAST data and constituted the first satellite detection of artificially excited Alfvénic ULF waves. The downward electron flux data for this event contain the first observations of electrons undergoing acceleration within the Ionospheric Alfvén Resonator (IAR) due to parallel electric fields associated with an artificially stimulated Alfvén wave. The time history and spectral content of the observed down-ward electron fluxes is investigated by considering the effects of a localised parallel electric field. Furthermore, it is demonstrated that a power law electron energy distribution describes the time-variable observed fluxes better than a Maxwellian distribution. Key words. Ionosphere (active experiments; particle acceleration) – Magnetospheric physics (electric fields)