Skip to Main content Skip to Navigation
Journal articles

Cluster survey of the mid-altitude cusp – Part 2: Large-scale morphology

Abstract : In this second part of our statistical study of the mid-altitude cusp, we compare the cusp morphology, as seen in the Cluster ion spectrometer (CIS), to the interplanetary magnetic field (IMF) orientation. We first recall the method we have used a) to define the cusp properties, b) to sort IMF conditions or behaviour in classes, c) to determine the proper time delay between the solar wind monitors and Cluster. Then, we define a few morphological features of the cusp and we relate these to the prevailing IMF. Our results reveal, among other things, that the occurrence of clearly dispersed ion structures in the cusp is 48%. From these dispersions, we infer the distance to reconnection site, which we relate to external conditions. In all other cases, the cusp exhibits a more disturbed behaviour in terms of ion structures and fall in our "discontinuous" or "irregular" categories. Among these, a few interesting cases of discontinuous cusps occurring under stable IMF conditions have been identified. They all occur when the IMF is dominated by its Y-component, which plays in principle in favour of anti-parallel reconnection but their wide MLT and latitudinal distributions is a priori incompatible with the anti-parallel reconnection hypothesis solely.
Document type :
Journal articles
Complete list of metadatas

Cited literature [47 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-00363647
Contributor : Béatrice Pibaret-Bourdon <>
Submitted on : Thursday, August 27, 2020 - 2:24:01 PM
Last modification on : Monday, August 31, 2020 - 11:20:32 AM

File

angeo-27-1875-2009.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Collections

Citation

Frederic Pitout, C. P. Escoubet, B. Klecker, I. Dandouras. Cluster survey of the mid-altitude cusp – Part 2: Large-scale morphology. Annales Geophysicae, European Geosciences Union, 2009, 27 (5), pp.1875-1886. ⟨10.5194/angeo-27-1875-2009⟩. ⟨insu-00363647⟩

Share

Metrics

Record views

150

Files downloads

27