Oblique propagation of nonlinear hydromagnetic waves: One- and two-dimensional behavior

Malara, F; Elaoufir, J

doi:10.1029/90JA01588

Title: Oblique propagation of nonlinear hydromagnetic waves: One- and two-dimensional behavior

Full Record
Other Related Research

Abstract

The one- and two-dimensional behavior of obliquely propagating hydromagnetic waves is analyzed by means of analytical theory and numerical simulations. It is shown that the nonlinear evolution of a one-dimensional MHD wave leads to the formation of a rotational discontinuity and a compressive steepened quasi-linearly polarized pulse whose structure is similar to that of a finite amplitude magnetosonic simple wave. For small propagation angles, the pulse mode (fast or slow) depends on the value of {beta} with respect to unity while for large propagation angles the wave mode is fixed by the sign of the initial density-field correlation. The two-dimensional evolution shows that an MHD wave is unstable against a small-amplitude long-wavelength modulation in the direction transverse to the wave propagation direction. A two-dimensional magnetosonic wave solution is found, in which the density fluctuation is driven by the corresponding total pressure fluctuation, exactly as in the one-dimensional simple wave. Along with the steepening effect, the wave experiences both wave front deformation and a self-focusing effect which may eventually lead to the collapse of the wave. The results compare well with observations of MHD waves in the Earth's foreshock and at comets.

Authors:

Malara, F ^[1]; Elaoufir, J ^[2]

Univ. della Calabria, Cosenza (Italy)
Observatoire de Paris-Meudon (France)

Publication Date:: Wed May 01 00:00:00 EDT 1991

OSTI Identifier:: 5186759

Resource Type:: Journal Article

Journal Name:: Journal of Geophysical Research; (United States)

Additional Journal Information:: Journal Volume: 96:A5; Journal ID: ISSN 0148-0227

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; HYDROMAGNETIC WAVES; WAVE PROPAGATION; ANALYTICAL SOLUTION; COMETS; COMPARATIVE EVALUATIONS; EARTH MAGNETOSPHERE; INTERACTIONS; IONS; MAGNETOACOUSTIC WAVES; NONLINEAR PROBLEMS; PLASMA DENSITY; REFLECTION; SOLAR WIND; WAVE FORMS; CHARGED PARTICLES; EARTH ATMOSPHERE; EVALUATION; SOLAR ACTIVITY; 640201* - Atmospheric Physics- Auroral, Ionospheric, & Magetospheric Phenomena; 640107 - Astrophysics & Cosmology- Planetary Phenomena

Citation Formats


                    Malara, F, and Elaoufir, J. Oblique propagation of nonlinear hydromagnetic waves: One- and two-dimensional behavior.  United States: N. p., 1991. 
        Web.  doi:10.1029/90JA01588.

Copy to clipboard


                    Malara, F, & Elaoufir, J. Oblique propagation of nonlinear hydromagnetic waves: One- and two-dimensional behavior.  United States.  https://doi.org/10.1029/90JA01588

Copy to clipboard


                    Malara, F, and Elaoufir, J. 1991.  
        "Oblique propagation of nonlinear hydromagnetic waves: One- and two-dimensional behavior".  United States.  https://doi.org/10.1029/90JA01588.

Copy to clipboard


                    
@article{osti_5186759,

  title        = {Oblique propagation of nonlinear hydromagnetic waves: One- and two-dimensional behavior},

  author       = {Malara, F and Elaoufir, J},

  abstractNote = {The one- and two-dimensional behavior of obliquely propagating hydromagnetic waves is analyzed by means of analytical theory and numerical simulations. It is shown that the nonlinear evolution of a one-dimensional MHD wave leads to the formation of a rotational discontinuity and a compressive steepened quasi-linearly polarized pulse whose structure is similar to that of a finite amplitude magnetosonic simple wave. For small propagation angles, the pulse mode (fast or slow) depends on the value of {beta} with respect to unity while for large propagation angles the wave mode is fixed by the sign of the initial density-field correlation. The two-dimensional evolution shows that an MHD wave is unstable against a small-amplitude long-wavelength modulation in the direction transverse to the wave propagation direction. A two-dimensional magnetosonic wave solution is found, in which the density fluctuation is driven by the corresponding total pressure fluctuation, exactly as in the one-dimensional simple wave. Along with the steepening effect, the wave experiences both wave front deformation and a self-focusing effect which may eventually lead to the collapse of the wave. The results compare well with observations of MHD waves in the Earth's foreshock and at comets.},

  doi          = {10.1029/90JA01588},

  url          = {https://www.osti.gov/biblio/5186759},
  journal      = {Journal of Geophysical Research; (United States)},

  issn         = {0148-0227},

  number       = ,

  volume       = 96:A5,

  place        = {United States},

  year         = {Wed May 01 00:00:00 EDT 1991},

  month        = {Wed May 01 00:00:00 EDT 1991}

}

Copy to clipboard

Journal Article:

https://doi.org/10.1029/90JA01588

Other availability

Find in Google Scholar

Search WorldCat to find libraries that may hold this journal

Save / Share:

Export Metadata

Save to My Library

Similar records in OSTI.GOV collections:

Steepening of kinetic magnetosonic waves into shocklets: Simulations and consequences for planetary shocks and comets

Journal Article Omidi, N; Winske, D - Journal of Geophysical Research; (United States)

Numerical simulations are used to investigate the nonlinear evolution of oblique low-frequency electromagnetic (kiinetic magnetosonic) waves, which have been observed upstream of planetary bow shocks and at comet Giacobini-Zinner. The observations show that the waves are elliptically polarized and have a sinusoidal form when their amplitude is small, but they become steepend and linearly polarized as they grow in amplitude. These waves have been referred to as shocklets. A high-frequency whisterl wave packet is commonly seen at the steepened edge of the shocklets. To investigate the generation and the nonlinear evolution of kinetic magnetosonic waves in a self-consistent manner, anmore »« less
https://doi.org/10.1029/JA095iA03p02281
Steepened magnetosonic waves in the high. beta. plasma surrounding Comet Giacobini-Zinner

Conference Tsurutani, B; Smith, E; Thorne, R; ...

We extend the previous studies of intense hydromagnetic waves at Giacobini-Zinner to investigate the mode and direction of wave propagation. Simultaneous high-resolution measurements of electron density fluctuations demonstrate that the long period (approx.100 s) waves are propagating in the magnetosonic mode. Principal axis analyses of the long period waves and accompanying partial rotations show that the sum of the wave phase rotations is 360/sup 0/C, indicating that both are parts of the same wave oscillation. From the time sequence of the steepened waveforms observed by ICE, we demonstrate that the waves must propagate towards the sun with C/sub ph/ <more »« less
Full Text Available
Linear and nonlinear properties of ULF waves driven by ring-beam distribution functions

Journal Article Killen, K; Omidi, N; Karimabadi, H - Journal of Geophysical Research

The problem of the excitation of obliquely propagating magnetosonic waves which can steepen up (also known a shocklets) is considered. Shocklets have been observed upstream of the Earth`s bow shock and at comets Giacobini-Zinner and Grigg-Skjellerup. Linear theory as well as two-dimensional (2-D) hybrid (fluid electrons, particle ions) simulations are used to determine the properties of waves generated by ring-beam velocity distributions in great detail. The effects of both proton and oxygen ring-beams are considered. The study of instabilities excited by a proton ring-beam is relevant to the region upstream of the Earth`s bow shock, whereas the oxygen ring-beam correspondsmore »« less
https://doi.org/10.1029/94JA02899
Parameteric studies of nonlinear oblique magnetosonic waves in two-ion-species plasmas

Journal Article Toida, Mieko; Kondo, Yuichi - Physics of Plasmas

The study of the effects of ion composition on perpendicular magnetosonic waves in two-ion-species plasmas [M. Toida, H. Higashino, and Y. Ohsawa, J. Phys. Soc. Jpn. 76, 104052 (2007)] is extended to include oblique waves. First, the conditions necessary for KdV equations for low- and high-frequency modes to be valid are analytically obtained. The upper limit of the amplitude of the low-frequency-mode pulse is expressed as a function of the propagation angle {theta}, density ratio, and cyclotron frequency ratio of the two ion species. Next, with electromagnetic particle simulations, the nonlinear evolution of a long-wavelength low-frequency-mode disturbance is examined formore »« less
https://doi.org/10.1063/1.3596381
Nonlinear dynamics of small-scale Alfvén waves

Journal Article Mallet, Alfred; Dorfman, Seth; Abler, Mel; ... - Physics of Plasmas

Herein we study the nonlinear evolution of very oblique small-scale Alfvén waves with k_⊥d_i≳1. At these scales, the waves become significantly compressive, unlike in magnetohydrodynamics, due to the Hall term in the equations. We demonstrate that when frequencies are small compared to the ion gyrofrequency and amplitudes are small compared to unity, no new nonlinear interaction appears due to the Hall term alone at the lowest non-trivial order, even when k_⊥d_i~1. However, at the second non-trivial order, we discover that the Hall physics leads to a slow but resonant nonlinear interaction between co-propagating Alfvén waves, an inherently three-dimensional effect. Includingmore »« less
https://doi.org/10.1063/5.0151035

Similar Records