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Title: Conceptual study of moderately coupled plasmas and experimental comparison of laboratory x-ray sources

Abstract

In this thesis the fundamental concepts of moderately coupled plasmas, for which 2≲lnΛ b≲10, are, for the first time, presented. This investigation is motivated because neither the conventional Fokker-Planck approximation [for weakly coupled plasmas (lnΛ b≲10)] nor the theory of dielectric response with correlations for strongly coupled plasmas (lnΛ b≲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/lnΛ 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 ρR have been calculated for charged fusion products (α`s, 3H, 3He) 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-, andmore » N-lines) with wavelengths from 0.5 Å to 111 Å 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 ( < 3 keV). Finally, a direct comparisons of both sources (PIXE and electron-beam x-ray sources) to a commercially available radioactive α fluorescent x-ray source has been made.« less

Authors:
 [1]
  1. Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center
Publication Date:
Research Org.:
Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center; Lawrence Livermore National Lab., CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
140425
Report Number(s):
PFC/RR-93-6
ON: DE94005828; TRN: 94:014817
DOE Contract Number:
FG02-91ER54109; W-7405-ENG-48
Resource Type:
Thesis/Dissertation
Resource Relation:
Other Information: TH: Thesis (Ph.D.); PBD: Dec 1993
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; X-RAY SOURCES; DESIGN; COLLISIONAL PLASMA; CHARGED-PARTICLE TRANSPORT; RELAXATION LOSSES; COULOMB SCATTERING

Citation Formats

Li, Chikang. Conceptual study of moderately coupled plasmas and experimental comparison of laboratory x-ray sources. United States: N. p., 1993. Web. doi:10.2172/140425.
Li, Chikang. Conceptual study of moderately coupled plasmas and experimental comparison of laboratory x-ray sources. United States. doi:10.2172/140425.
Li, Chikang. 1993. "Conceptual study of moderately coupled plasmas and experimental comparison of laboratory x-ray sources". United States. doi:10.2172/140425. https://www.osti.gov/servlets/purl/140425.
@article{osti_140425,
title = {Conceptual study of moderately coupled plasmas and experimental comparison of laboratory x-ray sources},
author = {Li, Chikang},
abstractNote = {In this thesis the fundamental concepts of moderately coupled plasmas, for which 2≲lnΛb≲10, are, for the first time, presented. This investigation is motivated because neither the conventional Fokker-Planck approximation [for weakly coupled plasmas (lnΛb≲10)] nor the theory of dielectric response with correlations for strongly coupled plasmas (lnΛb≲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/lnΛb 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 ρR have been calculated for charged fusion products (α`s, 3H, 3He) 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 Å to 111 Å 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 ( < 3 keV). Finally, a direct comparisons of both sources (PIXE and electron-beam x-ray sources) to a commercially available radioactive α fluorescent x-ray source has been made.},
doi = {10.2172/140425},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1993,
month =
}

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