Identification of waves in the lower-hybrid frequency range in the scrape-off layer plasma of Alcator C-Mod

Shinya, Takahiro; Baek, Seung Gyou; Wallace, Gregory M.; Shiraiwa, Syunichi; Takase, Yuichi; Parker, Ronald R.; Bonoli, Paul T.; Brunner, Dan; Faust, Ian; LaBombard, Brian L.; Wukitch, Steve

doi:10.7910/DVN/NRNCW4

Title: Identification of waves in the lower-hybrid frequency range in the scrape-off layer plasma of Alcator C-Mod

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Abstract

Polarization resolved measurements of the parallel refractive index Nk ≡ ckk/ω of the driven RF waves in the lower hybrid (LH) range of frequencies are performed using arrays of RF magnetic probes in the scrape-off layer plasma of Alcator C-Mod. The measured Nk of the RF magnetic field component parallel to the background magnetic field is about -1.6, which corresponds to the peak of the launched LH Nk spectrum. Based on the wave dispersion relationship, this wave is identified as the LH slow wave. On the other hand, the RF magnetic field component perpendicular to the magnetic field is found to have a lower Nk of -1.2, and is detected only near the last closed flux surface. This wave is identified as the LH fast wave generated by slow-fast wave mode conversion.

Authors:

Shinya, Takahiro; Baek, Seung Gyou; Wallace, Gregory M.; Shiraiwa, Syunichi; Takase, Yuichi; Parker, Ronald R.; Bonoli, Paul T.; Brunner, Dan; Faust, Ian; LaBombard, Brian L.; Wukitch, Steve

OSTI

Publication Date:: Thu Jun 20 00:00:00 EDT 2019

DOE Contract Number:: FC02-99ER54512

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:: 1881425

DOI:: https://doi.org/10.7910/DVN/NRNCW4

Citation Formats


                    Shinya, Takahiro, Baek, Seung Gyou, Wallace, Gregory M., Shiraiwa, Syunichi, Takase, Yuichi, Parker, Ronald R., Bonoli, Paul T., Brunner, Dan, Faust, Ian, LaBombard, Brian L., and Wukitch, Steve. Identification of waves in the lower-hybrid frequency range in the scrape-off layer plasma of Alcator C-Mod.  United States: N. p., 2019. 
        Web.  doi:10.7910/DVN/NRNCW4.

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                    Shinya, Takahiro, Baek, Seung Gyou, Wallace, Gregory M., Shiraiwa, Syunichi, Takase, Yuichi, Parker, Ronald R., Bonoli, Paul T., Brunner, Dan, Faust, Ian, LaBombard, Brian L., & Wukitch, Steve. Identification of waves in the lower-hybrid frequency range in the scrape-off layer plasma of Alcator C-Mod.  United States.  doi:https://doi.org/10.7910/DVN/NRNCW4

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                    Shinya, Takahiro, Baek, Seung Gyou, Wallace, Gregory M., Shiraiwa, Syunichi, Takase, Yuichi, Parker, Ronald R., Bonoli, Paul T., Brunner, Dan, Faust, Ian, LaBombard, Brian L., and Wukitch, Steve. 2019.  
"Identification of waves in the lower-hybrid frequency range in the scrape-off layer plasma of Alcator C-Mod".  United States.  doi:https://doi.org/10.7910/DVN/NRNCW4.  https://www.osti.gov/servlets/purl/1881425. Pub date:Thu Jun 20 00:00:00 EDT 2019

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@article{osti_1881425,

  title        = {Identification of waves in the lower-hybrid frequency range in the scrape-off layer plasma of Alcator C-Mod},

  author       = {Shinya, Takahiro and Baek, Seung Gyou and Wallace, Gregory M. and Shiraiwa, Syunichi and Takase, Yuichi and Parker, Ronald R. and Bonoli, Paul T. and Brunner, Dan and Faust, Ian and LaBombard, Brian L. and Wukitch, Steve},

  abstractNote = {Polarization resolved measurements of the parallel refractive index Nk ≡ ckk/ω of the driven RF waves in the lower hybrid (LH) range of frequencies are performed using arrays of RF magnetic probes in the scrape-off layer plasma of Alcator C-Mod. The measured Nk of the RF magnetic field component parallel to the background magnetic field is about -1.6, which corresponds to the peak of the launched LH Nk spectrum. Based on the wave dispersion relationship, this wave is identified as the LH slow wave. On the other hand, the RF magnetic field component perpendicular to the magnetic field is found to have a lower Nk of -1.2, and is detected only near the last closed flux surface. This wave is identified as the LH fast wave generated by slow-fast wave mode conversion.},

  doi          = {10.7910/DVN/NRNCW4},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Jun 20 00:00:00 EDT 2019},

  month        = {Thu Jun 20 00:00:00 EDT 2019}

}

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DOI: https://doi.org/10.7910/DVN/NRNCW4

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