Energetic electron signatures in an active magnetotail plasma sheet

Davies, J.A., Dunlop, M.W., Perry, C.H., Lockwood, M. ORCID: https://orcid.org/0000-0002-7397-2172, Alexeev, I., Taylor, M.G.G.T., Fazakerley, A.N., Owen, C.J., Marchaudon, A., Friedel, R.H.W., Deng, X.H., Grande, M. and Daly, P.W. (2006) Energetic electron signatures in an active magnetotail plasma sheet. Advances in Space Research, 38 (8). pp. 1608-1614. ISSN 0273-1177 doi: 10.1016/j.asr.2006.02.012

Abstract/Summary

Particles with energies of tens to hundreds of keV provide a powerful diagnostic of the acceleration processes that characterise the Earth’s magnetosphere, in particular the highly dynamic nightside plasma sheet. Such energetic particles can be detected by the RAPID experiment, onboard the quartet of Cluster spacecraft. We present results from the study of a series of quasi-periodic, intense energetic electron signatures in the magnetotail revealed by RAPID Imaging Electron Spectrometer (IES) observations some 19 Earth radii (RE) downtail, associated with the passage of a highly geoeffective, high-speed solar wind stream. The RAPID-IES signatures – interpreted in combination with magnetic field and lower-energy electron measurements from the FGM and PEACE experiments on Cluster, respectively, and with reference to energetic electron observations from the CEPPAD-IES instrument on Polar – are understood in terms of repeated encounters of the Cluster spacecraft with the tail plasma sheet in response to the resultant tail reconfiguration in each of a series of substorms. We consider the Cluster response for two of these substorms (identified according to the conventional expansion phase onset indicators of particle injection at geosynchronous orbit and Pi2 pulsations at Earth) in terms of two possible tail configurations in which a Near-Earth Neutral Line forms either antisunward or sunward of the Cluster spacecraft. The latter scenario, in which the reconnection X-line is assumed to form sunward of Cluster and subsequently migrate downtail such that the spacecraft become engulfed in a tailward expanding plasma sheet, is shown to be more consistent with the observations.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/38578
Item Type	Article
Refereed	Yes
Divisions	No Reading authors. Back catalogue items Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
Publisher	Elsevier
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