Coupling of Micro- and Meso-Scale Processes During Early Stage Plasmaspheric Refilling

点击翻译按钮获取中文摘要

This study addresses the problem of ion-beam driven waves and their effects on the accumulation of ionospheric plasma in the outer plasmasphere. This addresses a major problem in magnetospheric physics, that is, the refilling of the plasmasphere following geomagnetic storms. The primary goal of the project is to firmly establish the methodology of the following basic paradigm and modeling approach assumes that as soon as the plasma flow parameters cross marginal stability conditions for the waves, the instabilities are triggered and clamp the flow near the conditions for marginal stability. Thus, from the waves and instability standpoint, the quasisteady state of the plasma is known a priori. When the macroscopic processes drive the plasma away form this state toward instability, we know the excess momentum and the directed kinetic energy which need to be thermalized by the instability process. This facilitates an easy calculation of the anomalous plasma transport coefficients to be included in a mesoscale model based on plasma transport equations without knowing the details of the instabilityprocess. This approach is termed the Anomalous Plasma Effects or APE model. The research strategy consists of 1) systematic determination of easy-to-use semiempirical relations for the marginal stability conditions for the plasma during the refilling situation, 2) small-scale particle- in-cell simulations to characterize plasma heating by the instabilities and to test the APE model, and 3) mesoscale modeling using two-stream hydrodynamic code including the anomalous transport coefficients.