A Current disruption mechanism in the keutral sheet for triggering substorm expansions
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A Current disruption mechanism in the keutral sheet for triggering substorm expansions

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Published by National Aeronautics and Space Administration in [Washington, DC? .
Written in English

Subjects:

  • Astrophysics.,
  • Cosmic dust.

Book details:

Edition Notes

StatementA.T.Y. Lui ... [et al.].
SeriesNASA contractor report -- 186260., NASA contractor report -- NASA CR-186260.
ContributionsLui, Anthony T. Y., United States. National Aeronautics and Space Administration.
The Physical Object
FormatMicroform
Pagination1 v.
ID Numbers
Open LibraryOL18033033M

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The required electric field strength is in the 10 mV/m range which is well within the observed electric field values detected in the neutral sheet during substorms. This finding can potentially account for the disruption of cross-tail current and its diversion to the ionosphere to form the substorm current wedge. @article{osti_, title = {A current disruption mechanism in the neutral sheet for triggering substorm expansions. A substorm expansion onset scenario is proposed based on this instability in which the relative drift between ions and electrons is primarily due to unmagnetized ions undergoing current sheet acceleration in the presence of a cross-tail electric field. We suggest that current disruption in the tail at substorm expansion onset is due to the combined effect of the KCS! in the neutral sheet and the LHDI outside the neutral sheet.

The current disruption is accompanied by a diversion of the cross-tall current into the ionosphere, forming a current wedge. The radial extent of current disruption has been estimated quantitatively for a small substorm to be ~ RE in the innermost portion of the current sheet [Lui, ]. In that model the substorm expansion phase is driven by the formation of a new near-Earth reconnection region. In contrast, the Current Sheet Disruption (CSD) model identifies the onset of an instability in the near-Earth current sheet as the trigger for the expansion by: 2. There are two competing views of substorm onset: the near-Earth neutral-line (NENL) model [1, 2] and near-Earth current disruption (NECD), the most extensive model for which is given by Lui [3]. While both models allow for reconnection at a near-Earth X-line (NEXL) during the substorm expansion phase, they differ as to the cause of substorm by: 4. A current disruption mechanism in the neutral sheet - A possible trigger for substorm expansions. By K. Papadopoulos, C. S. Wu, A. Mankofsky, can lead to a local reduction of the cross-tail current causing it to continue through the ionosphere to form a substorm current wedge. A substorm expansion onset scenario is proposed based on this.

A Current disruption mechanism in the neutral sheet for triggering substorm expansions. [Anthony T Y Lui; United States. National Aeronautics and Space Administration.;]. A current disruption mechanism in the neutral sheet for triggering substorm expansions. By A. Mankofsky, K. Papadopoulos, C. S. Wu, electric field strength is in the 10 mV/m range which is well within the observed electric field values detected in the neutral sheet during substorms. This finding can potentially account for the disruption.   Optical auroral measurements repeatedly reveal the existence of a transitional stage between a quiescent preexisting arc and its significant auroral expansion in a substorm onset. Such a transitional stage of substorm onset (TSSO) is characterized by a gradual intensification and the emergence of auroral beads, along the preexisting arc. However, Cited by: 1. [6] The formation of thin current sheets in the magnetotail is a time‐dependent process that is controlled by the interaction of the magnetosphere with the solar wind. The evolution during the growth phase of substorms is relatively slow compared to the rapid reconfiguration during the break‐up by: