Diffraction of radio-frequency waves by plasma turbulence in the edge of a tokamak

Valvis, S. I.; Papadopoulos, A. D.; Hizanidis, K.; Papagiannis, P.; Tsironis, C.; Ram, A. K.

doi:10.7910/DVN/EFKUUC

Title: Diffraction of radio-frequency waves by plasma turbulence in the edge of a tokamak

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Abstract

The Mie-Lorenz-Debye theory of scattering of radio frequency waves (RF) by filamentary structures in the edge of a tokamak plasma has been established in prior publications. These results have been verified. Theory and computations show that RF can be reflected, refracted, and diffracted by turbulence. Furthermore, the filamentary structures lead to side scattering of waves and excitation of wave modes different from the launched RF. It is important to quantify the overall effect of turbulence on the propagation of RF since efficiency of heating and current drive by RF waves depends upon the wave characteristics. The commonly used RF ranges vary from the low frequency ion-cyclotron (IC) waves, to medium frequency lower-hybrid (LH) waves, to high-frequency electron cyclotron (EC) waves with wavelengths respectively, large, comparable, or smaller than the radial dimensions of the filaments. Currently, we discuss the scattering as well as the forces exerted by different RF in the edge plasma. Also, we present a code for 3D full wave scattering analysis of arbitrary tensor permittivity and plasma density profiles. The study is applicable to ITER-like plasmas, as well as to plasmas in medium sized tokamaks such as TCV, ASDEX-U and DIII-D and high field concepts like SPARC.

Authors:

Valvis, S. I.; Papadopoulos, A. D.; Hizanidis, K.; Papagiannis, P.; Tsironis, C.; Ram, A. K.

OSTI

Publication Date:: Fri Nov 05 00:00:00 EDT 2021

DOE Contract Number:: FG02-91ER54109; SC0018090

Research Org.:: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center

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

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

OSTI Identifier:: 1886843

DOI:: https://doi.org/10.7910/DVN/EFKUUC

Citation Formats


                    Valvis, S. I., Papadopoulos, A. D., Hizanidis, K., Papagiannis, P., Tsironis, C., and Ram, A. K. Diffraction of radio-frequency waves by plasma turbulence in the edge of a tokamak.  United States: N. p., 2021. 
        Web.  doi:10.7910/DVN/EFKUUC.

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                    Valvis, S. I., Papadopoulos, A. D., Hizanidis, K., Papagiannis, P., Tsironis, C., & Ram, A. K. Diffraction of radio-frequency waves by plasma turbulence in the edge of a tokamak.  United States.  doi:https://doi.org/10.7910/DVN/EFKUUC

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                    Valvis, S. I., Papadopoulos, A. D., Hizanidis, K., Papagiannis, P., Tsironis, C., and Ram, A. K. 2021.  
"Diffraction of radio-frequency waves by plasma turbulence in the edge of a tokamak".  United States.  doi:https://doi.org/10.7910/DVN/EFKUUC.  https://www.osti.gov/servlets/purl/1886843. Pub date:Fri Nov 05 00:00:00 EDT 2021

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@article{osti_1886843,

  title        = {Diffraction of radio-frequency waves by plasma turbulence in the edge of a tokamak},

  author       = {Valvis, S. I. and Papadopoulos, A. D. and Hizanidis, K. and Papagiannis, P. and Tsironis, C. and Ram, A. K.},

  abstractNote = {The Mie-Lorenz-Debye theory of scattering of radio frequency waves (RF) by filamentary structures in the edge of a tokamak plasma has been established in prior publications. These results have been verified. Theory and computations show that RF can be reflected, refracted, and diffracted by turbulence. Furthermore, the filamentary structures lead to side scattering of waves and excitation of wave modes different from the launched RF. It is important to quantify the overall effect of turbulence on the propagation of RF since efficiency of heating and current drive by RF waves depends upon the wave characteristics. The commonly used RF ranges vary from the low frequency ion-cyclotron (IC) waves, to medium frequency lower-hybrid (LH) waves, to high-frequency electron cyclotron (EC) waves with wavelengths respectively, large, comparable, or smaller than the radial dimensions of the filaments. Currently, we discuss the scattering as well as the forces exerted by different RF in the edge plasma. Also, we present a code for 3D full wave scattering analysis of arbitrary tensor permittivity and plasma density profiles. The study is applicable to ITER-like plasmas, as well as to plasmas in medium sized tokamaks such as TCV, ASDEX-U and DIII-D and high field concepts like SPARC.},

  doi          = {10.7910/DVN/EFKUUC},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Fri Nov 05 00:00:00 EDT 2021},

  month        = {Fri Nov 05 00:00:00 EDT 2021}

}

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DOI: https://doi.org/10.7910/DVN/EFKUUC

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