scholarly journals THE NONLINEAR INTERACTION OF AN ELECTROMAGNETIC WAVE WITH A TIME-DEPENDENT PLASMA MEDIUM

1965 ◽  
Vol 43 (1) ◽  
pp. 38-56 ◽  
Author(s):  
Robert J. Papa
Keyword(s):  
Electromagnetic Wave ◽  
Plane Wave ◽  
Electron Temperature ◽  
Wave Field ◽  
Electron Density ◽  
Nonlinear Interaction ◽  
Time Dependent ◽  
Constitutive Relationship ◽  
Time Varying ◽  
Plasma Medium

A one-dimensional, inhomogeneous model is used to describe the nonlinear interaction of a radio-frequency plane wave with a time-varying plasma medium. A monochromatic plane wave is normally incident upon an electron density profile where the electron density gradients are shallow compared to a wavelength. Changes in electron temperature and electron density are induced which continually alter the pattern of electromagnetic energy deposition into the medium. The electron energy relaxation time is much longer than the period of the electromagnetic wave, so that the electron temperature does not follow the rapid variations in the impressed field. A nonlinear constitutive relationship is derived relating the macroscopic current density to the impressed electric vector, assuming that the wave field is almost monochromatic in the medium. The time-dependent response of the plasma medium may be found by numerically solving the energy-balance equations and the continuity equation for the electron gas. The spread in frequency of the electromagnetic wave field due to the time-varying electrical conductivity may be computed by employing the WKB approximation as a solution to the wave equation for a time-varying medium. Graphs are presented which represent the time-dependent response of the electron temperature and electron density as a function of the incident r-f. field amplitude.

The propagation of a transverse electromagnetic wave in a nonlinear, anisotropic, time-dependent plasma medium

1968 ◽  
Vol 46 (7) ◽  
pp. 889-905
Author(s):  
Robert J. Papa
Keyword(s):  
Energy Balance ◽  
Plane Wave ◽  
Electron Temperature ◽  
Electron Density ◽  
Balance Equation ◽  
Energy Balance Equation ◽  
Time Dependent ◽  
Time Varying ◽  
Circularly Polarized ◽  
Elliptically Polarized

In a previous paper, a one-dimensional, inhomogeneous model was considered in describing the nonlinear interaction of a radiofrequency plane wave with a time-varying plasma. This paper extends the analysis to the anisotropic case, in which an elliptically polarized plane wave incident upon an electron-density profile induces changes in the electron density and electron temperature. A d-c. magnetic field parallel to the electron-density gradients causes the elliptically polarized wave to split into two distinct modes, a right-hand circularly polarized and a left-hand circularly polarized mode. The two modes are coupled through an energy-balance equation that governs the behavior of the electron temperature. The time-dependent response of the plasma may be found by numerically integrating an energy-balance equation and a continuity equation. The solution to the wave equation for the time-varying, inhomogeneous, anisotropic medium may be obtained through the use of the WKB approximation. The time scales for electron-temperature and electron-density changes are found to vary with incident flux, incident-wave ellipticity, and appropriate normalized plasma parameters.

Ensemble estimation of polarization ellipse parameters

2007 ◽  
Vol 463 (2088) ◽  
pp. 3375-3394 ◽  
Author(s):  
A.T Walden ◽  
T Medkour
Keyword(s):  
Angular Distribution ◽  
Standard Deviation ◽  
Aspect Ratio ◽  
Plane Wave ◽  
Wave Field ◽  
Covariance Matrix ◽  
Time Instant ◽  
Azimuth Angle ◽  
Ensemble Estimation ◽  
Plane Wave Field

An ellipse describes the polarized part of a partially polarized quasi-monochromatic plane wave field. Its azimuth angle and aspect ratio are functions of the elements of the covariance matrix associated with the polarized part at a particular time instant. Given an ensemble of K independent samples at that time, the distributions of the estimators of these parameters are derived. The estimation is thus based on a sample ensemble at any time, and does not assume temporal stationarity. Additionally, the azimuth angle estimator has an angular distribution so that non-standard statistical methods are needed when deriving its mean and standard deviation.

ODE integration schemes for plane-wave real-time time-dependent density functional theory

2019 ◽  
Vol 150 (1) ◽  
pp. 014101 ◽  
Author(s):  
Daniel A. Rehn ◽  
Yuan Shen ◽  
Marika E. Buchholz ◽  
Madan Dubey ◽  
Raju Namburu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Plane Wave ◽  
Real Time ◽  
Density Functional ◽  
Time Dependent ◽  
Functional Theory ◽  
Integration Schemes ◽  
Dependent Density

Ion scale nonlinear interaction triggered by disparate scale electron temperature gradient mode

2015 ◽  
Vol 22 (5) ◽  
pp. 052301
Author(s):  
Chanho Moon ◽  
Tatsuya Kobayashi ◽  
Kimitaka Itoh ◽  
Rikizo Hatakeyama ◽  
Toshiro Kaneko
Keyword(s):  
Temperature Gradient ◽  
Electron Temperature ◽  
Nonlinear Interaction ◽  
Electron Temperature Gradient ◽  
Gradient Mode

Calculation of the electron density of the F region heated by a high-power radio-wave field

1977 ◽  
Vol 20 (12) ◽  
pp. 1267-1270 ◽  
Author(s):  
Yu. A. Ignat'ev ◽  
Z. N. Krotova ◽  
�. E. Mityakova
Keyword(s):  
Radio Wave ◽  
Wave Field ◽  
Electron Density ◽  
High Power ◽  
F Region

scholarly journals Comparison of the measured and modelled electron densities and temperatures in the ionosphere and plasmasphere during 20-30 January, 1993

2000 ◽  
Vol 18 (10) ◽  
pp. 1257-1262 ◽  
Author(s):  
A. V. Pavlov ◽  
T. Abe ◽  
K.-I. Oyama
Keyword(s):  
Magnetic Field ◽  
Heat Flux ◽  
Electron Temperature ◽  
Field Line ◽  
Electron Density ◽  
Magnetic Field Line ◽  
New Approach ◽  
Additional Heating ◽  
Vibrational Levels ◽  
The Magnetic Field

Abstract. We present a comparison of the electron density and temperature behaviour in the ionosphere and plasmasphere measured by the Millstone Hill incoherent-scatter radar and the instruments on board of the EXOS-D satellite with numerical model calculations from a time-dependent mathematical model of the Earth's ionosphere and plasmasphere during the geomagnetically quiet and storm period on 20–30 January, 1993. We have evaluated the value of the additional heating rate that should be added to the normal photoelectron heating in the electron energy equation in the daytime plasmasphere region above 5000 km along the magnetic field line to explain the high electron temperature measured by the instruments on board of the EXOS-D satellite within the Millstone Hill magnetic field flux tube in the Northern Hemisphere. The additional heating brings the measured and modelled electron temperatures into agreement in the plasmasphere and into very large disagreement in the ionosphere if the classical electron heat flux along magnetic field line is used in the model. A new approach, based on a new effective electron thermal conductivity coefficient along the magnetic field line, is presented to model the electron temperature in the ionosphere and plasmasphere. This new approach leads to a heat flux which is less than that given by the classical Spitzer-Harm theory. The evaluated additional heating of electrons in the plasmasphere and the decrease of the thermal conductivity in the topside ionosphere and the greater part of the plasmasphere found for the first time here allow the model to accurately reproduce the electron temperatures observed by the instruments on board the EXOS-D satellite in the plasmasphere and the Millstone Hill incoherent-scatter radar in the ionosphere. The effects of the daytime additional plasmaspheric heating of electrons on the electron temperature and density are small at the F-region altitudes if the modified electron heat flux is used. The deviations from the Boltzmann distribution for the first five vibrational levels of N2(v) and O2(v) were calculated. The present study suggests that these deviations are not significant at the first vibrational levels of N2 and O2 and the second level of O2, and the calculated distributions of N2(v) and O2(v) are highly non-Boltzmann at vibrational levels v > 2. The resulting effect of N2(v > 0) and O2(v > 0) on NmF2 is the decrease of the calculated daytime NmF2 up to a factor of 1.5. The modelled electron temperature is very sensitive to the electron density, and this decrease in electron density results in the increase of the calculated daytime electron temperature up to about 580 K at the F2 peak altitude giving closer agreement between the measured and modelled electron temperatures. Both the daytime and night-time densities are not reproduced by the model without N2(v > 0) and O2(v > 0), and inclusion of vibrationally excited N2 and O2 brings the model and data into better agreement.Key words: Ionosphere (ionospheric disturbances; ionosphere-magnetosphere interactions; plasma temperature and density)  

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