Design of a real-time two-color interferometer for MAST Upgrade

Naylor, G.; Scannell, R.; Cunningham, G.; Martin, R.; Croft, D.; Brunner, K. J.

doi:10.1063/1.4894394

Title: Design of a real-time two-color interferometer for MAST Upgrade

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Abstract

A single chord two-color CO{sub 2}/HeNe (10.6/0.633 μm) heterodyne laser interferometer has been designed to measure the line integral electron density along the mid-plane of the MAST Upgrade tokamak, with a typical error of 1 × 10{sup 18} m{sup −3} (∼2° phase error) at 4 MHz temporal resolution. To ensure this diagnostic system can be restored from any failures without stopping MAST Upgrade operations, it has been located outside of the machine area. The final design and initial testing of this system, including details of the optics, vibration isolation, and a novel phase detection scheme are discussed in this paper.

Authors:

Naylor, G.; Scannell, R.; Cunningham, G.; Martin, R.; Croft, D. ^[1]; Brunner, K. J. ^[2]

CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)
Centre for Advanced Instrumentation, Department of Physics, Durham University, DH1 3LE (United Kingdom)

Publication Date:: Sat Nov 15 00:00:00 EST 2014

OSTI Identifier:: 22303706

Resource Type:: Journal Article

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 85; Journal Issue: 11; Other Information: (c) 2014 Euratom; 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; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CARBON DIOXIDE; COLOR; DESIGN; DETECTION; ELECTRON DENSITY; ERRORS; HELIUM; INTERFEROMETERS; MAST TOKAMAK; MHZ RANGE 01-100; OPTICS; REAL TIME SYSTEMS; TESTING; TIME RESOLUTION

Citation Formats


                    O’Gorman, T., E-mail: thomas.ogorman@ccfe.ac.uk, Naylor, G., Scannell, R., Cunningham, G., Martin, R., Croft, D., and Brunner, K. J. Design of a real-time two-color interferometer for MAST Upgrade.  United States: N. p., 2014. 
        Web.  doi:10.1063/1.4894394.

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                    O’Gorman, T., E-mail: thomas.ogorman@ccfe.ac.uk, Naylor, G., Scannell, R., Cunningham, G., Martin, R., Croft, D., & Brunner, K. J. Design of a real-time two-color interferometer for MAST Upgrade.  United States.  https://doi.org/10.1063/1.4894394

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                    O’Gorman, T., E-mail: thomas.ogorman@ccfe.ac.uk, Naylor, G., Scannell, R., Cunningham, G., Martin, R., Croft, D., and Brunner, K. J. 2014.  
        "Design of a real-time two-color interferometer for MAST Upgrade".  United States.  https://doi.org/10.1063/1.4894394.

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@article{osti_22303706,

  title        = {Design of a real-time two-color interferometer for MAST Upgrade},

  author       = {O’Gorman, T., E-mail: thomas.ogorman@ccfe.ac.uk and Naylor, G. and Scannell, R. and Cunningham, G. and Martin, R. and Croft, D. and Brunner, K. J.},

  abstractNote = {A single chord two-color CO{sub 2}/HeNe (10.6/0.633 μm) heterodyne laser interferometer has been designed to measure the line integral electron density along the mid-plane of the MAST Upgrade tokamak, with a typical error of 1 × 10{sup 18} m{sup −3} (∼2° phase error) at 4 MHz temporal resolution. To ensure this diagnostic system can be restored from any failures without stopping MAST Upgrade operations, it has been located outside of the machine area. The final design and initial testing of this system, including details of the optics, vibration isolation, and a novel phase detection scheme are discussed in this paper.},

  doi          = {10.1063/1.4894394},

  url          = {https://www.osti.gov/biblio/22303706},
  journal      = {Review of Scientific Instruments},

  issn         = {0034-6748},

  number       = 11,

  volume       = 85,

  place        = {United States},

  year         = {Sat Nov 15 00:00:00 EST 2014},

  month        = {Sat Nov 15 00:00:00 EST 2014}

}

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