Collisional dependence of Alfven mode saturation in tokamaks

Zhou, M.; White, R.

doi:10.11578/1367170

Title: Collisional dependence of Alfven mode saturation in tokamaks

Abstract

Saturation of \alfven modes driven unstable by a distribution of high energy particles as a function of collisionality is investigated with a guiding center code, using numerical eigenfunctions produced by linear theory and numerical high energy particle distributions. The most important resonance is found and it is shown that when the resonance domain is bounded, not allowing particles to collisionlessly escape, the saturation amplitude is given by the balance of the resonance mixing time with the time for nearby particles to collisionally diffuse across the resonance width. Saturation amplitudes are in agreement with theoretical predictions as long as the mode amplitude is not so large that it produces stochastic loss from the resonance domain.

Authors:

Zhou, M.;

Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Publication Date:: 2016-12-01

DOE Contract Number:: AC02-09CH11466

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

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

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; TAE modes Saturation Tokamaks

Keywords:: TAE modes Saturation Tokamaks

OSTI Identifier:: 1367170

DOI:: https://doi.org/10.11578/1367170

Citation Formats


                    Zhou, M., and White, R. Collisional dependence of Alfven mode saturation in tokamaks.  United States: N. p., 2016. 
        Web.  doi:10.11578/1367170.

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                    Zhou, M., & White, R. Collisional dependence of Alfven mode saturation in tokamaks.  United States.  doi:https://doi.org/10.11578/1367170

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                    Zhou, M., and White, R. 2016.  
"Collisional dependence of Alfven mode saturation in tokamaks".  United States.  doi:https://doi.org/10.11578/1367170.  https://www.osti.gov/servlets/purl/1367170. Pub date:Thu Dec 01 00:00:00 EST 2016

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@article{osti_1367170,

  title        = {Collisional dependence of Alfven mode saturation in tokamaks},

  author       = {Zhou, M. and White, R.},

  abstractNote = {Saturation of \alfven modes driven unstable by a distribution of high energy particles as a function of collisionality is investigated with a guiding center code, using numerical eigenfunctions produced by linear theory and numerical high energy particle distributions. The most important resonance is found and it is shown that when the resonance domain is bounded, not allowing particles to collisionlessly escape, the saturation amplitude is given by the balance of the resonance mixing time with the time for nearby particles to collisionally diffuse across the resonance width. Saturation amplitudes are in agreement with theoretical predictions as long as the mode amplitude is not so large that it produces stochastic loss from the resonance domain.},

  doi          = {10.11578/1367170},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {2016},

  month        = {12}

}

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DOI: https://doi.org/10.11578/1367170

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Works referenced in this record:

Collisional dependence of Alfvén mode saturation in tokamaks
journal, October 2016

Zhou, Muni; White, Roscoe
Plasma Physics and Controlled Fusion, Vol. 58, Issue 12
https://doi.org/10.1088/0741-3335/58/12/125006

Works referencing / citing this record:

Collisional dependence of Alfvén mode saturation in tokamaks
journal, October 2016

Zhou, Muni; White, Roscoe
Plasma Physics and Controlled Fusion, Vol. 58, Issue 12
https://doi.org/10.1088/0741-3335/58/12/125006

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Title: Collisional dependence of Alfven mode saturation in tokamaks

Abstract

Citation Formats

Collisional dependence of Alfvén mode saturation in tokamaks journal, October 2016

Collisional dependence of Alfvén mode saturation in tokamaks journal, October 2016

Collisional dependence of Alfvén mode saturation in tokamaks
journal, October 2016

Collisional dependence of Alfvén mode saturation in tokamaks
journal, October 2016