Full Text

Turn on search term navigation

Copyright Copernicus GmbH 2011

Abstract

Oscillations with periods on the order of 5-10 min have been observed by instrumented spacecrafts in the Earth's magnetosphere. These oscillations often follow sudden impacts related to coronal mass ejections. It is demonstrated that a simple model is capable of explaining these oscillations and give a scaling law for their basic characteristics in terms of the basic parameters of the problem. The period of the oscillations and their anharmonic nature, in particular, are accounted for. The model has no free adjustable numerical parameters. The results agree well with observations. The analysis is supported by numerical simulations solving the Magneto-Hydro-Dynamic (MHD) equations in two spatial dimensions, where we let a solar wind interact with a magnetic dipole representing a magnetized Earth. We consider two tilt-angles of the magnetic dipole axis. We find the formation of a magnetosheath with the magnetopause at a distance corresponding well to the analytical results. Sudden pulses in the model solar wind sets the model magnetosphere into damped oscillatory motions and quantitatively good agreement with the analytical results is achieved.

Details

Title
Minute-scale period oscillations of the magnetosphere
Author
Børve, S.; Sato, H.; Pécseli, H. L.; Trulsen, J. K.
First page
663
Publication year
2011
Publication date
2011
Publisher
Copernicus GmbH
ISSN
0992-7689
e-ISSN
14320576
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
869915936
Copyright
Copyright Copernicus GmbH 2011