Van Allen Probes Bibliography is from August 2012 through September 2021 Notice:
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Outward radial diffusion driven by losses at magnetopause
Author | Shprits, Y; Thorne, R.; Friedel, R.; Reeves, G.; Fennell, J.; Baker, D.; Kanekal, S.; |
Keywords | Magnetopause Losses |
Abstract | Loss mechanisms responsible for the sudden depletions of the outer electron radiation belt are examined based on observations and radial diffusion modeling, with L*-derived boundary conditions. SAMPEX data for October\textendashDecember 2003 indicate that depletions often occur when the magnetopause is compressed and geomagnetic activity is high, consistent with outward radial diffusion for L* > 4 driven by loss to the magnetopause. Multichannel Highly Elliptical Orbit (HEO) satellite observations show that depletions at higher L occur at energies as low as a few hundred keV, which excludes the possibility of the electromagnetic ion cyclotron (EMIC) wave-driven pitch angle scattering and loss to the atmosphere at L* > 4. We further examine the viability of the outward radial diffusion loss by comparing CRRES observations with radial diffusion model simulations. Model-data comparison shows that nonadiabatic flux dropouts near geosynchronous orbit can be effectively propagated by the outward radial diffusion to L* = 4 and can account for the main phase depletions of outer radiation belt electron fluxes. |
Year of Publication | 2006 |
Journal | Journal of Geophysical Research |
Volume | 111 |
Number of Pages | |
Section | |
Date Published | 11/2006 |
ISBN | |
URL | http://onlinelibrary.wiley.com/doi/10.1029/2006JA011657/abstract |
DOI | 10.1029/2006JA011657 |