Details

Autor(en) / Beteiligte

• Malaspina, David M.
• Wygant, John R.
• Ergun, Robert E.
• Reeves, Geoff D.
• Skoug, Ruth M.
• Larsen, Brian A.

Titel

Electric field structures and waves at plasma boundaries in the inner magnetosphere

Ist Teil von

• Journal of geophysical research. Space physics, 2015-06, Vol.120 (6), p.4246-4263

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2015

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Recent observations by the Van Allen Probes spacecraft have demonstrated that a variety of electric field structures and nonlinear waves frequently occur in the inner terrestrial magnetosphere, including phase space holes, kinetic field line resonances, nonlinear whistler mode waves, and several types of double layer. However, it is unclear whether such structures and waves have a significant impact on the dynamics of the inner magnetosphere, including the radiation belts and ring current. To make progress toward quantifying their importance, this study statistically evaluates the correlation of such structures and waves with plasma boundaries. A strong correlation is found. These statistical results, combined with observations of electric field activity at propagating plasma boundaries, are consistent with the scenario that the sources of the free energy for the structures and waves of interest are localized near and comove with these boundaries. Therefore, the ability of these structures and waves to influence plasma in the inner magnetosphere is governed in part by the spatial extent and dynamics of macroscopic plasma boundaries in that region. Key Points Electric field structures and waves preferentially appear at boundaries Regions of electric field structure and wave growth comove with boundaries Data support an Alfvénic wave free energy source rather than boundary gradients