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 motionthe generalized azimuthal momentummakes 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 singlepass 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:
 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 03672921, 31, 10781086 (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 motionthe generalized azimuthal momentummakes 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 singlepass 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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