Role of Inductive Electric Field on the Build-up of Storm Time Ring Current
Abstract
During geomagnetic storms, plasma is energized and transported from the night side plasma sheet to the inner magnetosphere, resulting in a build-up of plasma density and pressure. The magnetic gradient-curvature further drives the energetic ions westward, therefore creating a pressure accumulation in the evening sector. Continuous inward adiabatic transport from the plasma sheet to the inner magnetosphere can be a major contributor to the pressure build up on night side, which suggests that convection electric field plays a significant role in developing the storm time ring current. However, during the storm time, the inductive nature can overwhelm the electrostatic nature of convection electric field, due to the temporal change of magnetic field. Thus, regarding the electrostatic component of electric field as the total convection field is not sufficient nor accurate for modeling the dynamics of inner magnetosphere system, and it may lead to mis-estimation of the transport and energization of ring current hot ion species, and associated storm time ring current build-up. Both theoretical and numerical modifications to an inner magnetosphere kinetic model --- Hot Electron-Ion Drift Integrator (HEIDI) has been made to account for the effect of inductive electric field, in order to assess how much inductive electric is relative to electro-static field, in addition with investigating the role of inductive electric field on the build-up and evolution of storm time inner magnetospheric ring current. We found that, during the intensifying southward IMF period, magnetic field is stretched away from dipole, and the associated inductive electric field further accumulates ion pressure in the evening sector and depletes ion pressure in the morning sector. The reverse is true as the magnetic field dipolarizes back to dipole configuration.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMSM037..11L
- Keywords:
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- 2730 Magnetosphere: inner;
- MAGNETOSPHERIC PHYSICS;
- 2736 Magnetosphere/ionosphere interactions;
- MAGNETOSPHERIC PHYSICS;
- 2772 Plasma waves and instabilities;
- MAGNETOSPHERIC PHYSICS;
- 2778 Ring current;
- MAGNETOSPHERIC PHYSICS