Modification of Alfvén wave dispersion and Alfvén wave heating in multiple ion species tokamak plasmas

It is shown that the existence of plasma density inhomogeneities (ducts) elongated along the magnetic field in coronal loops, and of Alfven wave dispersion, associated with the taking into account of gyrotropy U ≡ ω/ωi ≪ 1 (Leonovich et al., 1983), leads to the possibility of a quasi-longitudinal k⊥ < √U k‖ propagation (wave guiding) of Alfven waves. Here ω is the frequency of Alfven waves, ωi is the proton gyrofrequency, and k is the wave number. It is found that with the parameter ξ = ω2 R/ωi A > 1, where R is the inhomogeneity scale of a loop across the magnetic field, and A is the Alfven wave velocity, refraction of Alfven waves does not lead, as contrasted to Wentzel's inference (1976), to the waves going out of the regime of quasi-longitudinal propagation. As the result, the amplification of Alfven waves in solar coronal loops can be important. A study is made of the cyclotron instability of Alfven waves under solar coronal conditions.

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Plasma Heating by Alfvén Waves - Kinetic Properties of Magnetohydrodynamic Disturbances

Symposium - International Astronomical Union ◽

10.1017/s0074180900075860 ◽

1985 ◽

Vol 107 ◽

pp. 381-389

Author(s):

Akira Hasegawa

Keyword(s):

Electric Field ◽

Plasma Heating ◽

Alfven Wave ◽

Larmor Radius ◽

Alfvén Waves ◽

Kinetic Properties ◽

Parallel Electric Field ◽

Astrophysical Plasmas ◽

Finite Larmor Radius ◽

Wave Heating

Mechanisms of Alfvén wave heating in space-astrophysical plasmas are presented with particular emphasis on the parallel electric field generated in the magnetohydrodynamic perturbations due to the finite Larmor radius effects.

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Concerning the Dynamics of Energetic Protons in Coronal Magnetic Loops: Dispersion Effects of Alfven Waves

Symposium - International Astronomical Union ◽

10.1017/s0074180900076105 ◽

1985 ◽

Vol 107 ◽

pp. 559-559

Author(s):

V. A. Mazur ◽

A. V. Stepanov

Keyword(s):

Magnetic Field ◽

Wave Dispersion ◽

Alfven Waves ◽

Alfven Wave ◽

Wave Number ◽

Alfvén Waves ◽

Coronal Loops ◽

Coronal Magnetic Loops ◽

The Magnetic Field ◽

Solar Coronal

It is shown that the existence of plasma density inhomogeneities (ducts) elongated along the magnetic field in coronal loops, and of Alfven wave dispersion, associated with the taking into account of gyrotropy U ≡ ω/ωi ≪ 1 (Leonovich et al., 1983), leads to the possibility of a quasi-longitudinal k⊥ < √U k‖ propagation (wave guiding) of Alfven waves. Here ω is the frequency of Alfven waves, ωi is the proton gyrofrequency, and k is the wave number. It is found that with the parameter ξ = ω2 R/ωi A > 1, where R is the inhomogeneity scale of a loop across the magnetic field, and A is the Alfven wave velocity, refraction of Alfven waves does not lead, as contrasted to Wentzel's inference (1976), to the waves going out of the regime of quasi-longitudinal propagation. As the result, the amplification of Alfven waves in solar coronal loops can be important. A study is made of the cyclotron instability of Alfven waves under solar coronal conditions.

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A comparison of shielded and unshielded antennas for Alfven wave heating in a Tokamak

Plasma Physics and Controlled Fusion ◽

10.1088/0741-3335/30/10/010 ◽

1988 ◽

Vol 30 (10) ◽

pp. 1331-1338 ◽

Cited By ~ 5

Author(s):

M J Ballico ◽

M H Brennan ◽

R C Cross ◽

J A Lehane ◽

M L Sawley

Keyword(s):

Alfven Wave ◽

Wave Heating

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