A comparison between soft x-ray and magnetic phase data on the Madison symmetric torus

Reusch, L. M.; Sarff, J. S.; Den Hartog, D. J.; Franz, P.

doi:10.1063/1.4960492

Title: A comparison between soft x-ray and magnetic phase data on the Madison symmetric torus

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Abstract

The Soft X-Ray (SXR) tomography system on the Madison Symmetric Torus uses four cameras to determine the emissivity structure of the plasma. This structure should directly correspond to the structure of the magnetic field; however, there is an apparent phase difference between the emissivity reconstructions and magnetic field reconstructions when using a cylindrical approximation. The difference between the phase of the dominant rotating helical mode of the magnetic field and the motion of the brightest line of sight for each SXR camera is dependent on both the camera viewing angle and the plasma conditions. Holding these parameters fixed, this phase difference is shown to be consistent over multiple measurements when only toroidal or poloidal magnetic field components are considered. These differences emerge from physical effects of the toroidal geometry which are not captured in the cylindrical approximation.

Authors:

Reusch, L. M.; Sarff, J. S.; Den Hartog, D. J. ^[1]; Franz, P. ^[2]

University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)
Consorzio RFX, Padova (Italy)

Publication Date:: Tue Nov 15 00:00:00 EST 2016

OSTI Identifier:: 22596504

Resource Type:: Journal Article

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 87; Journal Issue: 11; Other Information: (c) 2016 Author(s); 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; APPROXIMATIONS; CAMERAS; COMPARATIVE EVALUATIONS; CYLINDRICAL CONFIGURATION; EMISSIVITY; GEOMETRY; MAGNETIC FIELDS; PLASMA; SOFT X RADIATION; SYMMETRY; TOMOGRAPHY

Citation Formats


                    VanMeter, P. D., E-mail: pvanmeter@wisc.edu, Reusch, L. M., Sarff, J. S., Den Hartog, D. J., and Franz, P. A comparison between soft x-ray and magnetic phase data on the Madison symmetric torus.  United States: N. p., 2016. 
        Web.  doi:10.1063/1.4960492.

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                    VanMeter, P. D., E-mail: pvanmeter@wisc.edu, Reusch, L. M., Sarff, J. S., Den Hartog, D. J., & Franz, P. A comparison between soft x-ray and magnetic phase data on the Madison symmetric torus.  United States.  https://doi.org/10.1063/1.4960492

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                    VanMeter, P. D., E-mail: pvanmeter@wisc.edu, Reusch, L. M., Sarff, J. S., Den Hartog, D. J., and Franz, P. 2016.  
        "A comparison between soft x-ray and magnetic phase data on the Madison symmetric torus".  United States.  https://doi.org/10.1063/1.4960492.

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@article{osti_22596504,

  title        = {A comparison between soft x-ray and magnetic phase data on the Madison symmetric torus},

  author       = {VanMeter, P. D., E-mail: pvanmeter@wisc.edu and Reusch, L. M. and Sarff, J. S. and Den Hartog, D. J. and Franz, P.},

  abstractNote = {The Soft X-Ray (SXR) tomography system on the Madison Symmetric Torus uses four cameras to determine the emissivity structure of the plasma. This structure should directly correspond to the structure of the magnetic field; however, there is an apparent phase difference between the emissivity reconstructions and magnetic field reconstructions when using a cylindrical approximation. The difference between the phase of the dominant rotating helical mode of the magnetic field and the motion of the brightest line of sight for each SXR camera is dependent on both the camera viewing angle and the plasma conditions. Holding these parameters fixed, this phase difference is shown to be consistent over multiple measurements when only toroidal or poloidal magnetic field components are considered. These differences emerge from physical effects of the toroidal geometry which are not captured in the cylindrical approximation.},

  doi          = {10.1063/1.4960492},

  url          = {https://www.osti.gov/biblio/22596504},
  journal      = {Review of Scientific Instruments},

  issn         = {0034-6748},

  number       = 11,

  volume       = 87,

  place        = {United States},

  year         = {Tue Nov 15 00:00:00 EST 2016},

  month        = {Tue Nov 15 00:00:00 EST 2016}

}

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