Kinetic Turbulence in the Terrestrial Magnetosheath: Cluster Observations
Abstract
We present a first statistical study of subproton and electron scales turbulence in the terrestrial magnetosheath using the Cluster Search Coil Magnetometer (SCM) waveforms of the STAFF instrument measured in the frequency range [1,180] Hz. It is found that clear spectral breaks exist near the electron scale, which separate two power-law like frequency bands referred to as the dispersive and the electron dissipation ranges. The frequencies of the breaks f_b are shown to be well correlated with the electron gyroscale \rho_e rather than with the electron inertial length de. The distribution of the slopes below fb was found to be narrow and peaks near -2.9, while that of the slopes above fb was found broader, peaks near -5.2 and has values as low as -7.5. This is the first time that such steep power-law spectra are reported in space plasma turbulence. These observations provide strong constraints on theoretical modeling of kinetic turbulence and dissipation in collisionless magnetized plasmas.
Keywords
Cite
@article{arxiv.1312.5167,
title = {Kinetic Turbulence in the Terrestrial Magnetosheath: Cluster Observations},
author = {S. Y. Huang and F. Sahraoui and X. H. Deng and J. S. He and Z. G. Yuan and M. Zhou and Y. Pang and H. S. Fu},
journal= {arXiv preprint arXiv:1312.5167},
year = {2015}
}
Comments
13 pages, 6 figures, submitted