insu-01408841
https://insu.hal.science/insu-01408841
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https://insu.hal.science/insu-01408841/file/2007_BeamPlasmaInteractionInRandomlyInhomogeneousPlasmasAndStatisticalPropertiesOfSmallAmplitudeLangmuirWvesInTheSolarWindAndElectronForeshock_JGR.pdf
doi:10.1029/2006JA012212
[OBSPM] Observatoire de Paris
[INSU] INSU - Institut National des Sciences de l'Univers
[CNRS] CNRS - Centre national de la recherche scientifique
[UNIV-ORLEANS] Université d'Orléans
[CNES] CNES - Centre national d'études spatiales
[OSUC] Observatoire des Sciences de l'Univers en région Centre
[LPC2E] Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
[PSL] Université Paris sciences et lettres
[OBSPM-PSL] Observatoire de Paris - PSL
Beam-plasma interaction in randomly inhomogeneous plasmas and statistical properties of small-amplitude Langmuir waves in the solar wind and electron foreshock
Krasnoselskikh, K,
Lobzin, V,
Musatenko, K
Soucek, J,
Pickett, J,
Cairns, I,
[SDU] Sciences of the Universe [physics]
ART
[1] A numerical model for wave propagation in an unstable plasma with inhomogeneities is developed. This model describes the linear interaction of Langmuir wave packets with an electron beam and takes into account the angular diffusion of the wave vector due to wave scattering on small-amplitude density fluctuations, as well as suppression of the instability caused by the removal of the wave from the resonance with particles during crossing density perturbations of relatively large amplitude. Using this model, the evolution of the wave packets in inhomogeneous plasmas with an electron beam is studied. To analyze data obtained both in space experiments and numerical modeling, a Pearson technique was used to classify the spectral density distributions. It was shown that both experimental distributions obtained within the Earth's foreshock aboard the CLUSTER spacecraft and model distributions for the logarithm of wave intensity belong to Pearson type IV rather than normal. The main reason for deviations of empirical distributions from the normal one is that the effective number of regions where the waves grow is not very large and, as a consequence, the central limit theorem fails to be true under the typical conditions for the Earth's electron foreshock. For large amplitudes, it is suggested that power law tails can result from variations of wave amplitudes due to changes of group velocity in the inhomogeneous plasma, in particular due to reflection of waves from inhomogeneities. Citation: Krasnoselskikh, V. V., V. V. Lobzin, K. Musatenko, J. Soucek, J. S. Pickett, and I. H. Cairns (2007), Beam-plasma interaction in randomly inhomogeneous plasmas and statistical properties of small-amplitude Langmuir waves in the solar wind and electron foreshock,
2007
2016-12-05
en
Journal of Geophysical Research Space Physics
American Geophysical Union/Wiley