O–X mode conversion in a non-symmetric torus at electron cyclotron frequencies

Weitzner, Harold

doi:10.1063/1.4975079

Title: O–X mode conversion in a non-symmetric torus at electron cyclotron frequencies

Abstract

Previous work on this topic, [Weitzner, Phys. Plasmas 11, 866 (2004)], applicable in a system with toroidal symmetry, is here extended to the case of a non-symmetric background equilibrium state. Maxwell's equations with the cold plasma dielectric tensor are used to represent the plasma-electromagnetic wave interaction. Away from the mode conversion region, geometrical optics adequately characterizes the wave propagation. A new, simpler derivation of the wave equations in the mode conversion region is given. Aside from one very special case in which a general plasma equilibrium behaves like a stratified medium, the previous results apply and highly effective mode conversion is found. The matching of the mode conversion solution to the geometrical optics solution, not previously examined, is discussed. A relatively weak condition on the perpendicular wave number near the resonance layer is found. Provided that the perpendicular wave number is small, it tends to zero at the mode conversion layer and the solutions match effectively.

Authors:

^[1]

New York Univ. (NYU), NY (United States). Courant Inst. of Mathematical Sciences

Publication Date:: Wed Feb 08 00:00:00 EST 2017

Research Org.:: New York Univ. (NYU), NY (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Contributing Org.:: Max Planck Inst. for Plasma Physics, Greifswald, (Germany)

OSTI Identifier:: 1465479

Alternate Identifier(s):: OSTI ID: 1349335

Grant/Contract Number:: FG02-86ER53233

Resource Type:: Accepted Manuscript

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 24; Journal Issue: 2; Journal ID: ISSN 1070-664X

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; geometrical optics; dielectrics; Maxwell equations; frequency analyzers; solution processes; tensor methods; plasma waves; numerical solutions; wave propagation; wave equations

Citation Formats


                    Weitzner, Harold. O–X mode conversion in a non-symmetric torus at electron cyclotron frequencies.  United States: N. p., 2017. 
Web.  doi:10.1063/1.4975079.

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                    Weitzner, Harold. O–X mode conversion in a non-symmetric torus at electron cyclotron frequencies.  United States.  https://doi.org/10.1063/1.4975079

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                    Weitzner, Harold. Wed .  
"O–X mode conversion in a non-symmetric torus at electron cyclotron frequencies".  United States.  https://doi.org/10.1063/1.4975079.  https://www.osti.gov/servlets/purl/1465479.

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@article{osti_1465479,

  title        = {O–X mode conversion in a non-symmetric torus at electron cyclotron frequencies},

  author       = {Weitzner, Harold},

  abstractNote = {Previous work on this topic, [Weitzner, Phys. Plasmas 11, 866 (2004)], applicable in a system with toroidal symmetry, is here extended to the case of a non-symmetric background equilibrium state. Maxwell's equations with the cold plasma dielectric tensor are used to represent the plasma-electromagnetic wave interaction. Away from the mode conversion region, geometrical optics adequately characterizes the wave propagation. A new, simpler derivation of the wave equations in the mode conversion region is given. Aside from one very special case in which a general plasma equilibrium behaves like a stratified medium, the previous results apply and highly effective mode conversion is found. The matching of the mode conversion solution to the geometrical optics solution, not previously examined, is discussed. A relatively weak condition on the perpendicular wave number near the resonance layer is found. Provided that the perpendicular wave number is small, it tends to zero at the mode conversion layer and the solutions match effectively.},

  doi          = {10.1063/1.4975079},

  journal      = {Physics of Plasmas},

  number       = 2,

  volume       = 24,

  place        = {United States},

  year         = {Wed Feb 08 00:00:00 EST 2017},

  month        = {Wed Feb 08 00:00:00 EST 2017}

}

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Works referenced in this record:

Electron Bernstein Wave Emission from an Overdense Plasma at the W7-AS Stellarator
journal, September 1998

Laqua, H. P.; Hartfuß, H. J.
Physical Review Letters, Vol. 81, Issue 10
DOI: 10.1103/PhysRevLett.81.2060

Electron-Bernstein-Wave Current Drive in an Overdense Plasma at the Wendelstein 7-AS Stellarator
journal, February 2003

Laqua, H. P.; Maassberg, H.; Marushchenko, N. B.
Physical Review Letters, Vol. 90, Issue 7
DOI: 10.1103/PhysRevLett.90.075003

Conversion between cold plasma modes in an inhomogeneous plasma
journal, January 1979

Weitzner, Harold; Batchelor, D. B.
Physics of Fluids, Vol. 22, Issue 7
DOI: 10.1063/1.862747

Penetration of high-frequency waves into a weakly inhomogeneous magnetized plasma at oblique incidence and their transformation to Bernstein modes
journal, August 1973

Preinhaelter, J.; Kopecký, V.
Journal of Plasma Physics, Vol. 10, Issue 1
DOI: 10.1017/S0022377800007649

Resonant and Nonresonant Electron Cyclotron Heating at Densities above the Plasma Cutoff by O-X-B Mode Conversion at the W7-As Stellarator
journal, May 1997

Laqua, H. P.; Erckmann, V.; Hartfuß, H. J.
Physical Review Letters, Vol. 78, Issue 18
DOI: 10.1103/PhysRevLett.78.3467

O-X mode conversion in an axisymmetric plasma at electron cyclotron frequencies
journal, March 2004

Weitzner, Harold
Physics of Plasmas, Vol. 11, Issue 3
DOI: 10.1063/1.1642655

Analytical solution of the O–X mode conversion problem
journal, April 2010

Volpe, Francesco
Physics Letters A, Vol. 374, Issue 15-16
DOI: 10.1016/j.physleta.2010.02.009

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Similar Records

Title: O–X mode conversion in a non-symmetric torus at electron cyclotron frequencies

Abstract

Citation Formats

Electron Bernstein Wave Emission from an Overdense Plasma at the W7-AS Stellarator journal, September 1998

Electron-Bernstein-Wave Current Drive in an Overdense Plasma at the Wendelstein 7-AS Stellarator journal, February 2003

Conversion between cold plasma modes in an inhomogeneous plasma journal, January 1979

Penetration of high-frequency waves into a weakly inhomogeneous magnetized plasma at oblique incidence and their transformation to Bernstein modes journal, August 1973

Resonant and Nonresonant Electron Cyclotron Heating at Densities above the Plasma Cutoff by O-X-B Mode Conversion at the W7-As Stellarator journal, May 1997

O-X mode conversion in an axisymmetric plasma at electron cyclotron frequencies journal, March 2004

Analytical solution of the O–X mode conversion problem journal, April 2010

Electron Bernstein Wave Emission from an Overdense Plasma at the W7-AS Stellarator
journal, September 1998

Electron-Bernstein-Wave Current Drive in an Overdense Plasma at the Wendelstein 7-AS Stellarator
journal, February 2003

Conversion between cold plasma modes in an inhomogeneous plasma
journal, January 1979

Penetration of high-frequency waves into a weakly inhomogeneous magnetized plasma at oblique incidence and their transformation to Bernstein modes
journal, August 1973

Resonant and Nonresonant Electron Cyclotron Heating at Densities above the Plasma Cutoff by O-X-B Mode Conversion at the W7-As Stellarator
journal, May 1997

O-X mode conversion in an axisymmetric plasma at electron cyclotron frequencies
journal, March 2004

Analytical solution of the O–X mode conversion problem
journal, April 2010