Author: Chi-Kang LiPublisher:
ISBN:
Category :
Languages : en
Pages : 13
Book Description
A Fokker-Planck Equation for Moderately Coupled Plasmas
Author: Chi-Kang LiExtension of Dougherty's Model Fokker-Planck Equation for a Plasma
Author: Robert J. PapaPublisher:
ISBN:
Category : Electromagnetic waves
Languages : en
Pages : 64
Book Description
Electromagnetic waves can be severely attenuated and suffer distortion as they propagate through partially ionized gases. These facts must be considered in the design of any communication system in which waves must propagate through an intervening plasma medium, such as in reentry communications and ionospheric propagation. In this report, formulas are given that can predict such wave attenuation characteristics more accurately and for a much wider range of plasma conditions than previous theories. The conventional Appleton-Hartree equation used in ionospheric propagation studies gives the index of refraction of a wave traveling through a plasma in a magnetic field in terms of the properties of the plasma. This conventional Appleton-Hartree formula neglects important effects such as the random thermal motion of the particles, which can produce nonlocal effects. Also, the energy dependence of the electron-neutral collision frequency can alter the nature of the wave attenuation process. A generalization of the Appleton-Hartree equation is made to include these effects and to account for the Coulomb forces between charged particles. A kinetic equation is solved which includes the effects of energy-dependent electron-neutral collisions, Coulomb encounters and spatial dispersion. The perturbation method used in solving the kinetic equation assumes that the effects of Coulomb encounters and spatial dispersion are dominant, and electron-neutral collisions are relatively infrequent.
Conceptual Study of Moderately Coupled Plasmas and Experimental Comparison of Laboratory X-ray Sources
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
In this thesis the fundamental concepts of moderately coupled plasmas, for which 2[approx-lt]ln[Lambda][sub b][approx-lt]10, are, for the first time, presented. This investigation is motivated because neither the conventional Fokker-Planck approximation [for weakly coupled plasmas (ln[Lambda][sub b][approx-lt]10)] nor the theory of dielectric response with correlations for strongly coupled plasmas (ln[Lambda][sub b][approx-lt]1) has satisfactorily addressed this regime. Specifically, herein the standard Fokker-Planck operator for Coulomb collisions has been modified to include hitherto neglected terms that are directly associated with large-angle scattering. In addition a reduced electron-ion collision operator has been calculated that, for the first time, manifests 1/ln[Lambda][sub b] corrections. Precise calculations of some relaxation rates and crude calculations of electron transport coefficients have been made. As one of major applications of the modified Fokker-Planck equation, the stopping powers and [rho]R have been calculated for charged fusion products ([alpha]'s, [sup 3]H, [sup 3]He) and hot electrons interacting with plasmas relevant to inertial confinement fusion. In the second major topic of this thesis, advances made in the area of laboratory x-ray sources are presented. First, and most importantly, through the use a Cockcroft-Walton linear accelerator, a charged particle induced x-ray emission (PIXE) source has been developed. Intense line x radiation (including K-, L-, M-, and N-lines) with wavelengths from 0.5 [angstrom] to 111 [angstrom] have been successfully produced. Second, a new high intensity electron-beam x-ray generator has also been developed, and it has been used with advantage in the soft x-ray region (
Model Fokker-Planck Equation for a Plasma and Its Solution
Author: Stanford University. Stanford Electronics LaboratoriesPublisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
Wave Motion in a Plasma Based on a Fokker-Planck Equation (Classic Reprint)
Author: Alan OppenheimPublisher: Forgotten Books
ISBN: 9780366501540
Category : Mathematics
Languages : en
Pages : 102
Book Description
Excerpt from Wave Motion in a Plasma Based on a Fokker-Planck Equation We introduce an isotropic approximation to the fokker-planck collision operators in Boltzmann's equations in order to study small amplitude wave motion in a fully ionized, neutral, two component plasma in a steady, applied magnetic field. With this model we find Larmor resonance modes which can not be found from theories based on the relaxation model of Bhatnagar, Gross and Krook[1] (the Krook model). We remark that so far the Krook model is the only other collision model from which one computes Larmor resonances. Moreover, these modes persist in a certain non-uniform collisionless limit. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Solution of a Spatially Dependent Fokker-Planck Equation for Mirror-confined Plasmas
Author: Kenneth Donald MarxKinetic Equations for Plasma and Radiation
Author: Albert SimonPublisher:
ISBN:
Category : Nuclear rediations
Languages : en
Pages : 46
Book Description
Steady states in plasma physics
Author: Klaus DresslerSteady States in Plasma Physics: the Vlasov-Fokker-Planck Equation
Author: K. DresslerWave Motion in a Plasma Based on a Fokker-Planck Equation
Author: Alan V. OppenheimPublisher:
ISBN:
Category : Fokker-Planck equation
Languages : en
Pages : 104
Book Description