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arXiv · 1908.11198

Observations of Electromagnetic Electron Holes and Evidence of Cherenkov Whistler Emission

Konrad Steinvall·Yuri V. Khotyaintsev·Daniel B. Graham·Andris Vaivads·Olivier Le Contel·Christopher T. Russell
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Abstract

We report observations of electromagnetic electron holes (EHs). We use multi-spacecraft analysis to quantify the magnetic field contributions of three mechanisms: the Lorentz transform, electron drift within the EH, and Cherenkov emission of whistler waves. The first two mechanisms account for the observed magnetic fields for slower EHs, while for EHs with speeds approaching half the electron Alfvén speed, whistler waves excited via the Cherenkov mechanism dominate the perpendicular magnetic field. The excited whistlers are kinetically damped and typically confined within the EHs.

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Konrad Steinvall, Yuri V. Khotyaintsev, Daniel B. Graham, Andris Vaivads, Olivier Le Contel, Christopher T. Russell. 2020-01-07. Observations of Electromagnetic Electron Holes and Evidence of Cherenkov Whistler Emission. https://doi.org/10.1103/physrevlett.123.255101

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