A model of electromagnetic electron phase-space holes and its application

J. B. Tao , R. E. Ergun , L. Andersson , J. W. Bonnell , A. Roux (1) , Olivier Le Contel (1) , V. Angelopoulos , J. P. Mcfadden , D. E. Larson , C. M. Cully , H.-U. Auster , K.-H. Glassmeier , W. Baumjohann , D. L. Newman , M. V. Goldman

1 LPP - Laboratoire de Physique des Plasmas

Electron phase-space holes (EHs) are indicators of nonlinear activities in space plasmas. Most often they are observed as electrostatic signals, but recently Andersson et al. [2009] reported electromagnetic EHs observed by the THEMIS mission in the Earth's plasma sheet. As a follow-up to Andersson et al. [2009], this paper presents a model of electromagnetic EHs where the deltaE × B₀ drift of electrons creates a net current. The model is examined with test-particle simulations and compared to the electromagnetic EHs reported by Andersson et al. [2009]. As an application of the model, we introduce a more accurate method than the simplified Lorentz transformation of Andersson et al. [2009] to derive EH velocity (v_EH). The sizes and potentials of EHs are derived from v_EH, so an accurate derivation of v_EH is important in analyzing EHs. In general, our results are qualitatively consistent with those of Andersson et al. [2009] but generally with smaller velocities and sizes.

Domaines: Astrophysique [astro-ph]; Physique des plasmas [physics.plasm-ph]

J. B. Tao, R. E. Ergun, L. Andersson, J. W. Bonnell, A. Roux, et al.. A model of electromagnetic electron phase-space holes and its application. Journal of Geophysical Research Space Physics, 2011, 116, pp.11213. ⟨10.1029/2010JA016054⟩. ⟨hal-01553742⟩