Far infrared fusion plasma diagnostics

Luhmann, Jr, N C; Peebles, W A

doi:10.2172/7011189

Title: Far infrared fusion plasma diagnostics

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Abstract

Over the last several years, reflectometry has grown in importance as a diagnostic for both steady-state density Profiles as well as for the investigation of density fluctuations and turbulence. As a diagnostic for density profile measurement, it is generally believed to be well understood in the tokamak environment. However, its use as a fluctuation diagnostic is hampered by a lack of quantitative experimental understanding of its wavenumber sensitivity and spatial resolution. Several researchers, have theoretically investigated these questions. However, prior to the UCLA laboratory investigation, no group has experimentally investigated these questions. Because of the reflectometer's importance to the world effort in understanding plasma turbulence and transport, UCLA has, over the last year, made its primary Task IIIA effort the resolution of these questions. UCLA has taken the lead in a quantitative experimental understanding of reflectometer data as applied to the measurement of density fluctuations. In addition to this, work has proceeded on the design, construction, and installation of a reflectometer system on UCLA's CCT tokamak. This effort will allow a comparison between the improved confinement regimes (H-mode) observed on both the DIII-D and CCT machines with the goal of achieving a physics understanding of the phenomena. Preliminary investigation ofmore »« less

Authors:: Luhmann, Jr, N C; Peebles, W A

Publication Date:: Mon Jan 01 00:00:00 EST 1990

Research Org.:: Univ. of California, Los Angeles, CA (United States)

Sponsoring Org.:: USDOE; USDOE, Washington, DC (United States)

OSTI Identifier:: 7011189

Report Number(s):: DOE/ER/53225-T6
ON: DE93002531

DOE Contract Number:: FG03-86ER53225

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; TOKAMAK DEVICES; PLASMA DIAGNOSTICS; DESIGN; FLUCTUATIONS; H-MODE PLASMA CONFINEMENT; INFRARED RADIATION; MEASURING INSTRUMENTS; PLASMA DENSITY; PROGRESS REPORT; REFLECTION; SCATTERING; TURBULENCE; CLOSED PLASMA DEVICES; CONFINEMENT; DOCUMENT TYPES; ELECTROMAGNETIC RADIATION; PLASMA CONFINEMENT; RADIATIONS; THERMONUCLEAR DEVICES; VARIATIONS; 700320* - Plasma Diagnostic Techniques & Instrumentation- (1992-)

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                    Luhmann, Jr, N C, and Peebles, W A. Far infrared fusion plasma diagnostics.  United States: N. p., 1990. 
        Web.  doi:10.2172/7011189.

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                    Luhmann, Jr, N C, & Peebles, W A. Far infrared fusion plasma diagnostics.  United States.  https://doi.org/10.2172/7011189

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                    Luhmann, Jr, N C, and Peebles, W A. 1990.  
        "Far infrared fusion plasma diagnostics".  United States.  https://doi.org/10.2172/7011189.  https://www.osti.gov/servlets/purl/7011189.

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@article{osti_7011189,

  title        = {Far infrared fusion plasma diagnostics},

  author       = {Luhmann, Jr, N C and Peebles, W A},

  abstractNote = {Over the last several years, reflectometry has grown in importance as a diagnostic for both steady-state density Profiles as well as for the investigation of density fluctuations and turbulence. As a diagnostic for density profile measurement, it is generally believed to be well understood in the tokamak environment. However, its use as a fluctuation diagnostic is hampered by a lack of quantitative experimental understanding of its wavenumber sensitivity and spatial resolution. Several researchers, have theoretically investigated these questions. However, prior to the UCLA laboratory investigation, no group has experimentally investigated these questions. Because of the reflectometer's importance to the world effort in understanding plasma turbulence and transport, UCLA has, over the last year, made its primary Task IIIA effort the resolution of these questions. UCLA has taken the lead in a quantitative experimental understanding of reflectometer data as applied to the measurement of density fluctuations. In addition to this, work has proceeded on the design, construction, and installation of a reflectometer system on UCLA's CCT tokamak. This effort will allow a comparison between the improved confinement regimes (H-mode) observed on both the DIII-D and CCT machines with the goal of achieving a physics understanding of the phenomena. Preliminary investigation of a new diagnostic technique to measure density profiles as a function of time has been initiated at UCLA. The technique promises to be a valuable addition to the range of available plasma diagnostics. Work on advanced holographic reflectometry technique as applied to fluctuation diagnostics has awaited a better understanding of the reflectometer signal itself as discussed above. Efforts to ensure the transfer of the diagnostic developments have continued with particular attention devoted to the preliminary design of a multichannel FIR interferometer for MST.},

  doi          = {10.2172/7011189},

  url          = {https://www.osti.gov/biblio/7011189},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Mon Jan 01 00:00:00 EST 1990},

  month        = {Mon Jan 01 00:00:00 EST 1990}

}

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