Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 1.585 IF 1.585
  • IF 5-year value: 1.698 IF 5-year
    1.698
  • CiteScore value: 1.62 CiteScore
    1.62
  • SNIP value: 0.820 SNIP 0.820
  • IPP value: 1.52 IPP 1.52
  • SJR value: 0.781 SJR 0.781
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 83 Scimago H
    index 83
  • h5-index value: 24 h5-index 24
Preprints
https://doi.org/10.5194/angeo-2020-25
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-2020-25
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Submitted as: angeo communicates 18 May 2020

Submitted as: angeo communicates | 18 May 2020

Review status
This preprint is currently under review for the journal ANGEO.

Wavevector spectral signature of decay instability in space plasmas

Horia Comisel1,2, Yasuhito Narita3, and Uwe Motschmann1,4 Horia Comisel et al.
  • 1Institut für Theoretische Physik, Technische Universität Braunschweig, Mendelssohnstr. 3, D-38106 Braunschweig, Germany
  • 2Institute for Space Sciences, Atomi ̧stilor 409, P.O. Box MG-23, Bucharest-M ̆agurele, RO-077125, Romania
  • 3Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, A-8042 Graz, Austria
  • 4Deutsches Zentrum für Luft- und Raumfahrt, Institut für Planetenforschung, Rutherfordstr. 2, D-12489 Berlin, Germany

Abstract. Identification of a large-amplitude Alfven wave decaying into a pair of ion-acoustic and daughter Alfven waves is one of the major goals in the observational studies of space plasma nonlinearity. In this study, the decay instability is analytically evaluated in the 2-D wavenumber domain spanning the parallel and perpendicular directions to the mean magnetic field. The growth-rate determination of the density perturbations is based on the Hall-MHD wave-wave coupling theory for circularly-polarized Alfven waves. The diagrams of the growth rates versus the wavenumber and propagation angle derived in analytical studies are replaced by 2-D wavenumber distributions and compared with the corresponding wavevector spectrum of density and magnetic field fluctuations. The actual study reveals a perpendicular-shape spectral pattern consistent with the result of a previous study based on 3-D hybrid numerical simulations. The wavevector signature of the decay instability observed in the two-dimensional wavenumber domain ceases at values of plasma beta larger than beta = 0.1. Growth-rate maps serve as a useful tool for predictions of the wavevector spectrum of density or magnetic field fluctuations in various scenarios for the wave-wave coupling processes developing at different stages in space plasma turbulence.

Horia Comisel et al.

Interactive discussion

Status: open (until 12 Jul 2020)
Status: open (until 12 Jul 2020)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Horia Comisel et al.

Horia Comisel et al.

Metrics will be available soon.
Latest update: 06 Jun 2020
Publications Copernicus
Download
Citation