scholarly journals Erratum: “Low-frequency surface waves on semi-bounded magnetized quantum plasma” [Phys. Plasmas 23, 084501 (2016)]

2018 ◽  
Vol 25 (5) ◽  
pp. 059901
Author(s):  
Afshin Moradi
Keyword(s):  
Surface Waves ◽  
Low Frequency ◽  
Plasma Phys ◽  
Quantum Plasma

Exchange interaction effects on low frequency surface waves in a quantum plasma slab

2017 ◽  
Vol 24 (5) ◽  
pp. 054505 ◽  
Author(s):  
M. Shahmansouri ◽  
B. Farokhi ◽  
R. Aboltaman
Keyword(s):  
Surface Waves ◽  
Exchange Interaction ◽  
Low Frequency ◽  
Interaction Effects ◽  
Quantum Plasma ◽  
Plasma Slab

scholarly journals Dispersion properties of electrostatic oscillations in quantum plasmas

2009 ◽  
Vol 76 (1) ◽  
pp. 7-17 ◽  
Author(s):  
BENGT ELIASSON ◽  
PADMA KANT SHUKLA
Keyword(s):  
Low Frequency ◽  
Electron Plasma ◽  
Quantum Plasma ◽  
Plasma Oscillations ◽  
Heisenberg Uncertainty Principle ◽  
Electrostatic Wave ◽  
Dense Plasmas ◽  
Astrophysical Objects ◽  
Heisenberg Uncertainty ◽  
Semiconductor Plasmas

AbstractWe present a derivation of the dispersion relation for electrostatic oscillations in a zero-temperature quantum plasma, in which degenerate electrons are governed by the Wigner equation, while non-degenerate ions follow the classical fluid equations. The Poisson equation determines the electrostatic wave potential. We consider parameters ranging from semiconductor plasmas to metallic plasmas and electron densities of compressed matter such as in laser compression schemes and dense astrophysical objects. Owing to the wave diffraction caused by overlapping electron wave function because of the Heisenberg uncertainty principle in dense plasmas, we have the possibility of Landau damping of the high-frequency electron plasma oscillations at large enough wavenumbers. The exact dispersion relations for the electron plasma oscillations are solved numerically and compared with the ones obtained by using approximate formulas for the electron susceptibility in the high- and low-frequency cases.

Fundamental properties of surface waves in lossless stratified structures

2010 ◽  
Vol 466 (2120) ◽  
pp. 2447-2469 ◽  
Author(s):  
Guido Valerio ◽  
David R. Jackson ◽  
Alessandro Galli
Keyword(s):  
Surface Waves ◽  
Dispersion Equation ◽  
High Frequency ◽  
Low Frequency ◽  
Layered Structures ◽  
Graphical Solution ◽  
Fundamental Properties ◽  
The Past ◽  
Permittivity And Permeability ◽  
Constitutive Parameters

This paper is focused on dispersive properties of lossless planar layered structures with media having positive constitutive parameters (permittivity and permeability), possibly uniaxially anisotropic. Some of these properties have been derived in the past with reference to specific simple layered structures, and are here established with more general proofs, valid for arbitrary layered structures with positive parameters. As a first step, a simple application of the Smith chart to the relevant dispersion equation is used to prove that evanescent (or plasmonic-type) waves cannot be supported by layers with positive parameters. The main part of the paper is then focused on a generalization of a common graphical solution of the dispersion equation, in order to derive some general properties about the behaviour of the wavenumbers of surface waves as a function of frequency. The wavenumbers normalized with respect to frequency are shown to be always increasing with frequency, and at high frequency they tend to the highest refractive index in the layers. Moreover, two surface waves with the same polarization cannot have the same wavenumber at a given frequency. The low-frequency behaviours are also briefly addressed. The results are derived by means of a suitable application of Foster’s theorem.

Excitation of lower hybrid waves by electron beams in finite geometry plasmas. Part 2. Surface waves

1978 ◽  
Vol 19 (2) ◽  
pp. 295-299
Author(s):  
Réal R. J. Gagné ◽  
Magdi M. Shoucri
Keyword(s):  
Electron Beam ◽  
Surface Waves ◽  
Electron Beams ◽  
Low Frequency ◽  
Finite Geometry ◽  
Dispersion Relations ◽  
Lower Hybrid ◽  
Small Density ◽  
Hybrid Waves ◽  
Lower Hybrid Waves

The dispersion relations for the quasi-static lower hybrid surface waves are derived. Conditions for their existence and their linear excitation by a small density electron beam are discussed. Instabilities appearing in low-frequency surface waves are also discussed.

scholarly journals Reduced models accounting for parallel magnetic perturbations: gyrofluid and finite Larmor radius–Landau fluid approaches

2016 ◽  
Vol 82 (6) ◽  
Author(s):  
E. Tassi ◽  
P. L. Sulem ◽  
T. Passot
Keyword(s):  
Fluid Model ◽  
Collisionless Plasma ◽  
Low Frequency ◽  
Wave Model ◽  
Plasma Phys ◽  
Alfven Wave ◽  
Larmor Radius ◽  
Closure Relation ◽  
Reduced Models ◽  
Finite Larmor Radius

Reduced models are derived for a strongly magnetized collisionless plasma at scales which are large relative to the electron thermal gyroradius and in two asymptotic regimes. One corresponds to cold ions and the other to far sub-ion scales. By including the electron pressure dynamics, these models improve the Hall reduced magnetohydrodynamics (MHD) and the kinetic Alfvén wave model of Boldyrev et al. (2013 Astrophys. J., vol. 777, 2013, p. 41), respectively. We show that the two models can be obtained either within the gyrofluid formalism of Brizard (Phys. Fluids, vol. 4, 1992, pp. 1213–1228) or as suitable weakly nonlinear limits of the finite Larmor radius (FLR)–Landau fluid model of Sulem and Passot (J. Plasma Phys., vol 81, 2015, 325810103) which extends anisotropic Hall MHD by retaining low-frequency kinetic effects. It is noticeable that, at the far sub-ion scales, the simplifications originating from the gyroaveraging operators in the gyrofluid formalism and leading to subdominant ion velocity and temperature fluctuations, correspond, at the level of the FLR–Landau fluid, to cancellation between hydrodynamic contributions and ion finite Larmor radius corrections. Energy conservation properties of the models are discussed and an explicit example of a closure relation leading to a model with a Hamiltonian structure is provided.

Shallow seismic detection of the fault zone associated with a high scarp in southwestern Montana

2015 ◽  
Vol 3 (1) ◽  
pp. T25-T41
Author(s):  
Jose Pujol ◽  
Mervin J. Bartholomew ◽  
Andrew Mickelson ◽  
Michael Bone
Keyword(s):  
Surface Waves ◽  
Fault Zone ◽  
Synthetic Data ◽  
Low Frequency ◽  
Normal Fault ◽  
Actual Data ◽  
Southwestern Montana ◽  
Velocity Models ◽  
Reflection Data ◽  
High Pass

We collected shallow reflection data in southwestern Montana, USA, across a 5.4-m-high tectonic scarp. The goal was to image the normal fault associated with the scarp, observed in an adjacent trench. Processing of the data was challenging because the height of the scarp was comparable to the depths of the reflectors of interest. To find out how to proceed, we processed synthetic data generated using velocity models derived in part from actual shot gathers. The actual data are dominated by large-amplitude low-frequency surface waves, but clear high-frequency reflections are seen in the more distant geophones. Common-offset gathers for the raw and high-pass filtered data reveal sharp discontinuities in arrival times and a strong decrease in amplitudes, respectively, under the scarp. These changes in the wavefield are indicative of lateral variations in elastic properties and are consistent with the presence of a fault zone seen in the trench. The actual data were stacked after the surface waves were removed with a narrow f-k filter. Severe muting was applied to isolate the reflections seen in the high-pass filtered data. The stacked data reveal a clear and fairly continuous horizontal reflector on the downthrown side of the fault and more disrupted reflectors on the upthrown side, with truncated reflections and changes in amplitude roughly across the projection of the fault mapped in the trench. These observations are consistent with faulting and would be difficult to explain if the scarp were an erosional feature.

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