The effects of the location and the timing of local convection electric field enhancements in the formation of ion multiple-nose structures

Abstract. It is shown that narrow channels of high electric field are an effective mechanism for injecting plasma into the inner magnetosphere. Analytical expressions for the electric field cannot produce these channels of intense plasma flow, and thus, result in less entry and adiabatic energization of the plasma sheet into near-Earth space. For the ions, omission of these channels leads to an underprediction of the strength of the stormtime ring current and therefore, an underestimation of the geoeffectiveness of the storm event. For the electrons, omission of these channels leads to the inability to create a seed population of 10-100 keV electrons deep in the inner magnetosphere. These electrons can eventually be accelerated into MeV radiation belt particles. To examine this, the 1-7 May 1998 magnetic storm is studied with a plasma transport model by using three different convection electric field models: Volland-Stern, Weimer, and AMIE. It is found that the AMIE model can produce particle fluxes that are several orders of magnitude higher in the L = 2 – 4 range of the inner magnetosphere, even for a similar total cross-tail potential difference. Key words. Space plasma physics (charged particle motion and acceleration) – Magnetospheric physics (electric fields, storms and substorms)

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Effect of the large-scale convection electric field structure on the formation of thin ionization layers at high latitudes

Journal of Atmospheric and Terrestrial Physics ◽

10.1016/0021-9169(94)90221-6 ◽

1994 ◽

Vol 56 (3) ◽

pp. 401-415 ◽

Cited By ~ 10

Author(s):

W.A. Bristow ◽

B.J. Watkins

Keyword(s):

Electric Field ◽

Large Scale ◽

Field Structure ◽

High Latitudes ◽

Convection Electric Field

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Energetic ion injection and formation of the storm-time symmetric ring current

Annales Geophysicae ◽

10.5194/angeo-24-3547-2006 ◽

2006 ◽

Vol 24 (12) ◽

pp. 3547-3556 ◽

Cited By ~ 8

Author(s):

L. Xie ◽

Z. Y. Pu ◽

X. Z. Zhou ◽

S. Y. Fu ◽

Q.-G. Zong ◽

...

Keyword(s):

Electric Field ◽

Ring Current ◽

Particle Trajectory ◽

Three Dimensional ◽

Extensive Study ◽

Current Injection ◽

Ion Injection ◽

Convection Electric Field ◽

Trajectory Calculations ◽

Current Region

Abstract. An extensive study of ring current injection and intensification of the storm-time ring current is conducted with three-dimensional (3-D) test particle trajectory calculations (TPTCs). The TPTCs reveal more accurately the process of ring current injection, with the main results being the following: (1) an intense convection electric field can effectively energize and inject plasma sheet particles into the ring current region within 1–3 h. (2) Injected ions often follow chaotic trajectories in non-adiabatic regions, which may have implications in storm and ring current physics. (3) The shielding electric field, which arises as a consequence of enhanced convection and co-exists with the injection and convection electric field, may cause the original open trajectories of injected ions with higher energy to change into closed ones, thus playing a role in the formation of the symmetric ring current.

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