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Updated: Jun 22, 2026

Emission Spectroscopic Boundary Layer Investigation during Ablative Material Testing in Plasmatron
Published on: June 9, 2016
Observations of double layers in earth's plasma sheet
R E Ergun1, L Andersson, J Tao
1Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80309, USA.
Abstract:
We report the first direct observations of parallel electric fields (E_{ parallel}) carried by double layers (DLs) in the plasma sheet of Earth's magnetosphere. The DL observations, made by the THEMIS spacecraft, have E_{ parallel} signals that are analogous to those reported in the auroral region. DLs are observed during bursty bulk flow events, in the current sheet, and in plasma sheet boundary layer, all during periods of strong magnetic fluctuations. These observations imply that DLs are a universal process and that strongly nonlinear and kinetic behavior is intrinsic to Earth's plasma sheet.
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