Theory of parametric resonance in a current carrying magnetized plasma

1979 ◽  
Vol 22 (6) ◽  
pp. 1154 ◽  
Author(s):  
Yu. M. Aliev ◽  
V. Stefan
Keyword(s):  
Parametric Resonance ◽  
Magnetized Plasma ◽  
A Current

scholarly journals Sliding Contacts in Planetary Magnetospheres

Symmetry ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 283
Author(s):  
Elena Belenkaya ◽  
Igor Alexeev
Keyword(s):  
Large Scale ◽  
Strong Field ◽  
Magnetized Plasma ◽  
Sliding Contacts ◽  
Radio Emissions ◽  
Planetary Magnetospheres ◽  
Current Task ◽  
Surrounding Space ◽  
Non Local ◽  
A Current

In the planetary magnetospheres there are specific places connected with velocity breakdown, reconnection, and dynamo processes. Here we pay attention to sliding layers. Sliding layers are formed in the ionosphere, on separatrix surfaces, at the magnetopauses and boundaries of stellar astrospheres, and at the Alfvén radius in the equatorial magnetosphere of rapidly rotating strongly magnetized giant planets. Although sliding contacts usually occur in thin local layers, their influence on the global structure of the surrounding space is very great. Therefore, they are associated with non-local processes that play a key role on a large scale. There can be an exchange between different forms of energy, a generation of strong field-aligned currents and emissions, and an amplification of magnetic fields. Depending on the conditions in the magnetosphere of the planet/exoplanet and in the flow of magnetized plasma passing it, different numbers of sliding layers with different configurations appear. Some are associated with regions of auroras and possible radio emissions. The search for planetary radio emissions is a current task in the detection of exoplanets.

scholarly journals MAGNETIZED PLASMA PARAMETRIC RESONANCE IN NON-MONOCHROMATIC PUMP-WAVE

1979 ◽  
Vol 40 (C7) ◽  
pp. C7-557-C7-558
Author(s):  
Yu. M. Aliev ◽  
O. M. Gradov ◽  
V. Stefan
Keyword(s):  
Parametric Resonance ◽  
Pump Wave ◽  
Magnetized Plasma

Electron acoustic double layer in a current-carrying magnetized plasma

1988 ◽  
Vol 36 (10) ◽  
pp. 1009-1013 ◽  
Author(s):  
S. Sutradhar Das ◽  
S. Bujarbarua
Keyword(s):  
Double Layer ◽  
Magnetized Plasma ◽  
Electron Acoustic ◽  
A Current

EFFECT OF ION SHEATH ON RADIATION IN A MAGNETOIONIG MEDIUM: II. SOURCE CURRENT PERPENDICULAR TO THE MAGNETOSTATIC FIELD

1967 ◽  
Vol 45 (2) ◽  
pp. 279-299
Author(s):  
S. R. Seshadri ◽  
K. L. Bhatnagar
Keyword(s):  
Radiation Resistance ◽  
Free Space ◽  
Magnetized Plasma ◽  
Magnetostatic Field ◽  
Source Current ◽  
Point Electric Dipole ◽  
Two Peaks ◽  
Limiting Case ◽  
Finite Extent ◽  
A Current

The radiation characteristics of current sources situated along the axis of an infinite cylindrical column of free space and surrounded by a homogeneous, loss-free magnetoionic medium are discussed for the case in which the source current is perpendicular to the magnetostatic field. The static magnetic field is assumed to be parallel to the axis of the free-space column, which is an idealization of the ion sheath formed around the antenna in the ionosphere. Both a point electric dipole and a finite and continuous array of the same are investigated. The dependence of the radiation resistance of these sources on the frequency and the ion-sheath thickness is examined. Even in the limiting case of vanishing thickness of the ion sheath, the radiation resistances of these sources are found to be different from those corresponding to an unbounded plasma. In contrast to those in an unbounded magnetoplasma, the radiation resistance remains finite for all frequencies. For the source of finite extent having a current distribution that falls off sufficiently rapidly towards the ends, the radiation resistance is quite insensitive to the changes in the thickness of the ion sheath.The radiation-resistance curve, in general, has two peaks at the so-called dipolar resonant frequencies, which depend primarily on the strength of the magnetostatic field. These dipolar resonances, which are quite analogous to those in an axially magnetized plasma column, are found to become sharper as the radius of the free-space column becomes smaller.

Effect of Ionization on the Potential Disturbance of a Current-Carrying Magnetized Plasma Caused by a Metal Plate

1984 ◽  
Vol 23 (Part 1, No. 8) ◽  
pp. 1153-1154 ◽  
Author(s):  
Motoichi Kawaguchi ◽  
Shigeru Suzuki ◽  
Hiroyoshi Tanaka ◽  
Hiroshi Enjoji
Keyword(s):  
Metal Plate ◽  
Magnetized Plasma ◽  
A Current

scholarly journals Semi-analytic model for the electromagnetic field of a current-driven antenna in a cold, magnetized plasma

2020 ◽  
Vol 86 (4) ◽  
Author(s):  
J. Robertson
Keyword(s):  
Mathematical Model ◽  
Electromagnetic Field ◽  
General Solution ◽  
Near Field ◽  
Computation Time ◽  
Dipole Antenna ◽  
Point Sources ◽  
Magnetized Plasma ◽  
Vacuum Field ◽  
A Current

In this semi-analytic study we develop a mathematical model for determining the electromagnetic field due to a current-driven antenna immersed in a cold, magnetized plasma, valid for frequencies below the electron plasma frequency. At each point in the plasma, it is shown that the vacuum electric field of the antenna couples to the plasma conductivity tensor and acts as an infinitesimal source term to drive plasma currents – the total field is then found from the aggregate sum of these point sources, expressed as an integral across the vacuum field. A general solution is provided for both azimuthally symmetric cylindrical coordinates as well as a fully generalized Cartesian solution. As an example of how this general solution may be applied, we solve for the field due to an electric dipole antenna of length $\ell$ , aligned along the background field, at frequencies below the ion cyclotron frequency. It is found that the near field decays exponentially with increasing $k_{\bot }z$ , whereas the far field exhibits wave-like behaviour. The radiation zone exhibits propagation cones emanating from either end of the dipole, with a propagation angle that is consistent with past analytic studies of inertial Alfvén waves. The mathematical model presented here may be advantageous over other numerical methods, as it allows the user to solve parts of the problems analytically, thereby cutting down significantly on computation time, as well as offering physical insight into the system that may not be evident with other numerical solvers.

Resolving Crystallites in Zirconium Oxide Films

1969 ◽  
Vol 27 ◽  
pp. 140-141
Author(s):  
R.A. Ploc
Keyword(s):  
Electron Microscope ◽  
Inelastic Scattering ◽  
Zirconium Oxide ◽  
Oxide Films ◽  
Optic Axis ◽  
Objective Lens ◽  
Microscope Objective ◽  
Linear Optic ◽  
A Current ◽  
Microscope Objective Lens

The optic axis of an electron microscope objective lens is usually assumed to be straight and co-linear with the mechanical center. No reason exists to assume such perfection and, indeed, simple reasoning suggests that it is a complicated curve. A current centered objective lens with a non-linear optic axis when used in conjunction with other lenses, leads to serious image errors if the nature of the specimen is such as to produce intense inelastic scattering.

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