Electrostatic steepening of whistler waves
Space Physics
2018-05-16 v1
Abstract
We present surprising observations by the NASA Van Allen Probes spacecraft of whistler waves with substantial electric field power at harmonics of the whistler wave fundamental frequency. The wave power at harmonics is due to nonlinearly steepened whistler electrostatic field that becomes possible in the two-temperature electron plasma due to whistler wave coupling to the electron-acoustic mode. The simulation and analytical estimates show that the steepening takes a few tens of milliseconds. The hydrodynamic energy cascade to higher frequencies facilitates efficient energy transfer from cyclotron resonant electrons, driving the whistler waves, to lower energy electrons.
Cite
@article{arxiv.1801.09862,
title = {Electrostatic steepening of whistler waves},
author = {Ivan Y. Vasko and Oleksiy V. Agapitov and Forrest S. Mozer and John W. Bonnell and Anto V. Artemyev and Vladimir V. Krasnoselskikh and Yuguang Tong},
journal= {arXiv preprint arXiv:1801.09862},
year = {2018}
}