Evolution of electron pitch angle distributions following injection from the plasma sheet
Tao, X.; Thorne, R.M.; Li, W.; Ni, B.; Meredith, Nigel P.; Horne, Richard B.. 2011 Evolution of electron pitch angle distributions following injection from the plasma sheet. Journal of Geophysical Research, 116 (A4), A04229. 8, pp. 10.1029/2010JA016245Full text not available from this repository. (Request a copy)
The temporal evolution of the phase space density of plasma sheet electrons (100 eV-30 keV) injected into the nightside at L = 6 during moderate geomagnetic activity is investigated using a quasi-linear diffusion formulation. Scattering in energy and pitch angle during interactions with both whistler mode chorus waves and electron cyclotron harmonic waves are included using an improved wave model recently obtained using CRRES spacecraft data. We compare our simulation results with observations from the THEMIS spacecraft and demonstrate that the formation of the observed electron pitch angle distributions is mainly due to resonant interactions with a combination of upper and lower band chorus waves. The pancake distributions at low energies (E < 2 keV), the flattened pitch angle distributions at medium energies (between 2-3 keV), and the distributions with enhanced pitch angle anisotropy at high energies (E > 3 keV) are explained using the banded chorus wave structure with a power minimum at half the electron cyclotron frequency. Results of the current work can be used to model the dynamical evolution and resultant global distribution of plasma sheet electrons.
|Programmes:||BAS Programmes > Polar Science for Planet Earth (2009 - ) > Climate|
|NORA Subject Terms:||Atmospheric Sciences|
|Date made live:||20 Jun 2011 14:21|
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