American Geophysical Union Become an AGU Member
Subscribe to AGU Journals		 AGU Home AGU Publications

Read Full Article (file size: 314098 bytes)    Cited by

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 107, NO. A9, 1256, doi:10.1029/2001JA009148, 2002

Reconnection onset in the tail of Earth's magnetosphere

M. I. Sitnov

Department of Astronomy, University of Maryland at College Park, College Park, Maryland, USA


A. S. Sharma

Department of Astronomy, University of Maryland at College Park, College Park, Maryland, USA


P. N. Guzdar

Institute for Research in Electronics and Applied Physics, University of Maryland at College Park, Maryland, USA


P. H. Yoon

Institute for Physical Science and Technology, University of Maryland at College Park, College Park, Maryland, USA


Abstract

We present the nonlocal kinetic linear stability analysis of the self-consistent isotropic collisionless plasma equilibrium with strongly stretched magnetic field lines (the so-called modified Harris sheet) with respect to the tearing mode, which provides the onset of laminar reconnection in the system. The stability problem is solved using the finite element technique and the drift-kinetic description for the electron species with additional averaging over the bounce motion of the trapped electrons. The mode is found unstable for ion-to-electron temperature ratios typical for the tail current sheet of Earth's magnetosphere when this sheet is sufficiently long, so that the electrons leaving it may be treated as transient particles. Comparison of the theory with earlier fluid modeling shows that the onset of reconnection is controlled by the Hall effect and a purely kinetic effect arising from different responses of the trapped and transient electrons. Geophysical implications such as the formation of the near-Earth neutral line and thin current sheets during substorms are discussed.

Published 27 September 2002.

Index Terms: 2772 Magnetospheric Physics: Plasma waves and instabilities; 2744 Magnetospheric Physics: Magnetotail; 2788 Magnetospheric Physics: Storms and substorms; 3230 Mathematical Geophysics: Numerical solutions.

Read Full Article (file size: 314098 bytes)    Cited by

Citation: Sitnov, M. I., A. S. Sharma, P. N. Guzdar, and P. H. Yoon (2002), Reconnection onset in the tail of Earth's magnetosphere, J. Geophys. Res., 107(A9), 1256, doi:10.1029/2001JA009148.