Solitary Electromagnetic Pulses Detected with Super-Alfvénic Flows in Earth’s Geomagnetic Tail
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Author/Creator ORCID
Date
2007-06-27
Type of Work
Department
Program
Citation of Original Publication
Parks, G. K., E. Lee, N. Lin, F. Mozer, M. Wilber, I. Dandouras, H. Rème, et al. “Solitary Electromagnetic Pulses Detected with Super-Alfv\’enic Flows in Earth’s Geomagnetic Tail.” Physical Review Letters 98, no. 26 (June 27, 2007): 265001. https://doi.org/10.1103/PhysRevLett.98.265001.
Rights
This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
Public Domain Mark 1.0
Public Domain Mark 1.0
Subjects
Abstract
Solitary nonlinear ( δB=B >> 1) electromagnetic pulses have been detected in Earth’s geomagnetic tail
accompanying plasmas flowing at super-Alfvenic speeds. The pulses in the current sheet had durations of
∼5 s, were left-hand circularly polarized, and had phase speeds of approximately the Alfven speed in the
plasma frame. These pulses were associated with a field-aligned current Jₗₗ and observed in low density
(0:3 cm⁻³), high temperature (Te ∼ Ti ∼ 3 x 10⁷ K), and β ∼ 10 plasma that included electron and ion
beams streaming along B. The wave activity was enhanced from below the ion cyclotron frequency to
electron cyclotron and upper hybrid frequencies. The detailed properties suggest the pulses are nonlinearly steepened ion cyclotron or Alfven waves.