Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities

Park, H. K.; Yun, G. S.; Nam, Y. B.; Choe, G. H.; Lee, W.; Jardin, S.

doi:10.1063/1.4940030

Title: Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities

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Abstract

The electron cyclotron emission imaging (ECEI) instrument is widely used to study the local electron temperature (T{sub e}) fluctuations by measuring the ECE intensity I{sub ECE} ∝ T{sub e} in tokamak plasmas. The ECEI measurement is often processed in a normalized fluctuation quantity against the time averaged value due to complication in absolute calibration. In this paper, the ECEI channels are relatively calibrated using the flat T{sub e} assumption of the sawtooth crash or the tearing mode island and a proper extrapolation. The 2-D relatively calibrated electron temperature (T{sub e,rel}) images are reconstructed and the displacement amplitude of the magnetohydrodynamic modes can be measured for the accurate quantitative growth analysis.

Authors:

Park, H. K. ^[1]; Yun, G. S.; Nam, Y. B.; Choe, G. H. ^[2]; Lee, W. ^[3]; Jardin, S. ^[4]

National Fusion Research Institute, Daejeon 34133 (Korea, Republic of)
Pohang University of Science and Technology, Pohang, Gyeongbuk 790-784 (Korea, Republic of)
Ulsan National Institute of Science and Technology, Ulsan 689-798 (Korea, Republic of)
Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

Publication Date:: Fri Jan 15 00:00:00 EST 2016

OSTI Identifier:: 22482820

Resource Type:: Journal Article

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 87; Journal Issue: 1; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0034-6748

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CALIBRATION; CYCLOTRONS; ELECTRON TEMPERATURE; EMISSION; FLUCTUATIONS; PLASMA; SAWTOOTH OSCILLATIONS; TEARING INSTABILITY; TOKAMAK DEVICES

Citation Formats


                    Choi, M. J., E-mail: mjchoi@nfri.re.kr, Park, H. K., Ulsan National Institute of Science and Technology, Ulsan 689-798, Yun, G. S., Nam, Y. B., Choe, G. H., Lee, W., and Jardin, S. Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities.  United States: N. p., 2016. 
        Web.  doi:10.1063/1.4940030.

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                    Choi, M. J., E-mail: mjchoi@nfri.re.kr, Park, H. K., Ulsan National Institute of Science and Technology, Ulsan 689-798, Yun, G. S., Nam, Y. B., Choe, G. H., Lee, W., & Jardin, S. Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities.  United States.  https://doi.org/10.1063/1.4940030

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                    Choi, M. J., E-mail: mjchoi@nfri.re.kr, Park, H. K., Ulsan National Institute of Science and Technology, Ulsan 689-798, Yun, G. S., Nam, Y. B., Choe, G. H., Lee, W., and Jardin, S. 2016.  
        "Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities".  United States.  https://doi.org/10.1063/1.4940030.

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@article{osti_22482820,

  title        = {Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities},

  author       = {Choi, M. J., E-mail: mjchoi@nfri.re.kr and Park, H. K. and Ulsan National Institute of Science and Technology, Ulsan 689-798 and Yun, G. S. and Nam, Y. B. and Choe, G. H. and Lee, W. and Jardin, S.},

  abstractNote = {The electron cyclotron emission imaging (ECEI) instrument is widely used to study the local electron temperature (T{sub e}) fluctuations by measuring the ECE intensity I{sub ECE} ∝ T{sub e} in tokamak plasmas. The ECEI measurement is often processed in a normalized fluctuation quantity against the time averaged value due to complication in absolute calibration. In this paper, the ECEI channels are relatively calibrated using the flat T{sub e} assumption of the sawtooth crash or the tearing mode island and a proper extrapolation. The 2-D relatively calibrated electron temperature (T{sub e,rel}) images are reconstructed and the displacement amplitude of the magnetohydrodynamic modes can be measured for the accurate quantitative growth analysis.},

  doi          = {10.1063/1.4940030},

  url          = {https://www.osti.gov/biblio/22482820},
  journal      = {Review of Scientific Instruments},

  issn         = {0034-6748},

  number       = 1,

  volume       = 87,

  place        = {United States},

  year         = {Fri Jan 15 00:00:00 EST 2016},

  month        = {Fri Jan 15 00:00:00 EST 2016}

}

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