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Title: Particle Confinement in Axisymmetric Poloidal Magnetic Field Configurations with Zeros of B: Methodological Note

Abstract

Collisionless particle confinement in axisymmetric configurations with magnetic field nulls is analyzed. The existence of an invariant of motion--the generalized azimuthal momentum--makes it possible to determine in which of the spatial regions separated by magnetic separatrices passing through the magnetic null lines the particle occurs after it leaves the vicinity of a magnetic null line. In particular, it is possible to formulate a sufficient condition for the particle not to escape through the separatrix from the confinement region to the external region. In the configuration under analysis, the particles can be lost from a separatrix layer with a thickness on the order of the Larmor radius because of the nonconservation of the magnetic moment {mu}. In this case, the variations in {mu} are easier to describe in a coordinate system associated with the magnetic surfaces. An analysis is made of the applicability of expressions for the single-pass change {delta}{mu} in the magnetic moment that were obtained in different magnetic field models for a confinement system with a divertor (such that there is a circular null line)

Authors:
;  [1]
  1. Nuclear Fusion Institute, Russian Research Centre Kurchatov Institute, pl. Kurchatova 1, Moscow, 123182 (Russian Federation)
Publication Date:
OSTI Identifier:
20718856
Resource Type:
Journal Article
Resource Relation:
Journal Name: Plasma Physics Reports; Journal Volume: 31; Journal Issue: 12; Other Information: Translated from Fizika Plazmy, ISSN 0367-2921, 31, 1078-1086 (No. 12, 2005); DOI: 10.1134/1.2147646; (c) 2005 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA); TN:
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AXIAL SYMMETRY; DIVERTORS; LARMOR RADIUS; MAGNETIC FIELDS; MAGNETIC MOMENTS; MAGNETIC SURFACES; PLASMA; PLASMA CONFINEMENT; WALL EFFECTS

Citation Formats

Arsenin, V.V., and Skovoroda, A.A.. Particle Confinement in Axisymmetric Poloidal Magnetic Field Configurations with Zeros of B: Methodological Note. United States: N. p., 2005. Web. doi:10.1134/1.2147646.
Arsenin, V.V., & Skovoroda, A.A.. Particle Confinement in Axisymmetric Poloidal Magnetic Field Configurations with Zeros of B: Methodological Note. United States. doi:10.1134/1.2147646.
Arsenin, V.V., and Skovoroda, A.A.. Thu . "Particle Confinement in Axisymmetric Poloidal Magnetic Field Configurations with Zeros of B: Methodological Note". United States. doi:10.1134/1.2147646.
@article{osti_20718856,
title = {Particle Confinement in Axisymmetric Poloidal Magnetic Field Configurations with Zeros of B: Methodological Note},
author = {Arsenin, V.V. and Skovoroda, A.A.},
abstractNote = {Collisionless particle confinement in axisymmetric configurations with magnetic field nulls is analyzed. The existence of an invariant of motion--the generalized azimuthal momentum--makes it possible to determine in which of the spatial regions separated by magnetic separatrices passing through the magnetic null lines the particle occurs after it leaves the vicinity of a magnetic null line. In particular, it is possible to formulate a sufficient condition for the particle not to escape through the separatrix from the confinement region to the external region. In the configuration under analysis, the particles can be lost from a separatrix layer with a thickness on the order of the Larmor radius because of the nonconservation of the magnetic moment {mu}. In this case, the variations in {mu} are easier to describe in a coordinate system associated with the magnetic surfaces. An analysis is made of the applicability of expressions for the single-pass change {delta}{mu} in the magnetic moment that were obtained in different magnetic field models for a confinement system with a divertor (such that there is a circular null line)},
doi = {10.1134/1.2147646},
journal = {Plasma Physics Reports},
number = 12,
volume = 31,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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