Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak

Rhodes, Terry L.; Peebles, William A.; Crocker, Neal A.; Nguyen, X.

doi:10.1063/1.4887276

Title: Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak

Abstract

The design and performance of a new cross-polarization scattering (CPS) system for the localized measurement of internal magnetic fluctuations is presented. CPS is a process whereby magnetic fluctuations scatter incident electromagnetic radiation into a perpendicular polarization which is subsequently detected. A new CPS design that incorporates a unique scattering geometry was laboratory tested, optimized, and installed on the DIII-D tokamak. Plasma tests of signal-to-noise, polarization purity, and frequency response indicate proper functioning of the system. Lastly, CPS data show interesting features related to internal MHD perturbations known as sawteeth that are not observed on density fluctuations.

Authors:

Rhodes, Terry L. ^[1]; Peebles, William A. ^[1]; Crocker, Neal A. ^[1]; Nguyen, X. ^[1]

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

Publication Date:: Tue Aug 05 00:00:00 EDT 2014

Research Org.:: General Atomics, San Diego, CA (United States)

Sponsoring Org.:: USDOE Office of Nuclear Energy (NE)

OSTI Identifier:: 1352924

Grant/Contract Number:: FC02-04ER54698

Resource Type:: Accepted Manuscript

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 85; Journal Issue: 11; Journal ID: ISSN 0034-6748

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

Citation Formats


                    Rhodes, Terry L., Peebles, William A., Crocker, Neal A., and Nguyen, X. Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak.  United States: N. p., 2014. 
Web.  doi:10.1063/1.4887276.

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                    Rhodes, Terry L., Peebles, William A., Crocker, Neal A., & Nguyen, X. Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak.  United States.  https://doi.org/10.1063/1.4887276

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                    Rhodes, Terry L., Peebles, William A., Crocker, Neal A., and Nguyen, X. Tue .  
"Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak".  United States.  https://doi.org/10.1063/1.4887276.  https://www.osti.gov/servlets/purl/1352924.

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@article{osti_1352924,

  title        = {Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak},

  author       = {Rhodes, Terry L. and Peebles, William A. and Crocker, Neal A. and Nguyen, X.},

  abstractNote = {The design and performance of a new cross-polarization scattering (CPS) system for the localized measurement of internal magnetic fluctuations is presented. CPS is a process whereby magnetic fluctuations scatter incident electromagnetic radiation into a perpendicular polarization which is subsequently detected. A new CPS design that incorporates a unique scattering geometry was laboratory tested, optimized, and installed on the DIII-D tokamak. Plasma tests of signal-to-noise, polarization purity, and frequency response indicate proper functioning of the system. Lastly, CPS data show interesting features related to internal MHD perturbations known as sawteeth that are not observed on density fluctuations.},

  doi          = {10.1063/1.4887276},

  journal      = {Review of Scientific Instruments},

  number       = 11,

  volume       = 85,

  place        = {United States},

  year         = {Tue Aug 05 00:00:00 EDT 2014},

  month        = {Tue Aug 05 00:00:00 EDT 2014}

}

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Works referenced in this record:

Linear Mode Conversion by Magnetic Fluctuations in Inhomogeneous Magnetized Plasmas
journal, April 1989

Lehner, T.; Rax, J. M.; Zou, X. L.
Europhysics Letters (EPL), Vol. 8, Issue 8
DOI: 10.1209/0295-5075/8/8/009

Electromagnetic wave scattering from magnetic fluctuations in tokamaks
journal, March 1992

Vahala, Linda; Vahala, George; Bretz, N.
Physics of Fluids B: Plasma Physics, Vol. 4, Issue 3
DOI: 10.1063/1.860259

Doppler reflectometry for the investigation of propagating density perturbations
journal, January 2001

Hirsch, M.; Holzhauer, E.; Baldzuhn, J.
Review of Scientific Instruments, Vol. 72, Issue 1
DOI: 10.1063/1.1308998

Internal Magnetic Turbulence Measurement in Plasma by Cross Polarization Scattering
journal, August 1995

Zou, X. L.; Colas, L.; Paume, M.
Physical Review Letters, Vol. 75, Issue 6
DOI: 10.1103/PhysRevLett.75.1090

Microwave scattering near the cut-off layer by density and magnetic field fluctuations
journal, April 1994

Bruskin, L. G.; Mase, A.; Tamano, T.
Plasma Physics and Controlled Fusion, Vol. 36, Issue 4
DOI: 10.1088/0741-3335/36/4/009

Internal magnetic fluctuations and electron heat transport in the Tore Supra tokamak: Observation by cross-polarization scattering
journal, June 1998

Colas, L.; Zou, X. L.; Paume, M.
Nuclear Fusion, Vol. 38, Issue 6
DOI: 10.1088/0029-5515/38/6/308

Measurement of magnetic fluctuations of electromagnetic plasma waves by cross-polarization scattering
journal, January 1997

Mase, A.; Bruskin, L. G.; Oyama, N.
Review of Scientific Instruments, Vol. 68, Issue 1
DOI: 10.1063/1.1147905

Cross-polarization scattering from low-frequency electromagnetic waves in the GAMMA10 tandem mirror
journal, January 1999

Kogi, Y.; Mase, A.; Bruskin, L. G.
Review of Scientific Instruments, Vol. 70, Issue 1
DOI: 10.1063/1.1149423

Experiments on cross-polarization scattering in the upper hybrid resonance region
journal, June 2005

Gurchenko, A. D.; Gusakov, E. Z.; Larionov, M. M.
Plasma Physics Reports, Vol. 31, Issue 6
DOI: 10.1134/1.1947332

A novel, multichannel, comb-frequency Doppler backscatter system
journal, October 2010

Peebles, W. A.; Rhodes, T. L.; Hillesheim, J. C.
Review of Scientific Instruments, Vol. 81, Issue 10
DOI: 10.1063/1.3464266

Quasioptical design of integrated Doppler backscattering and correlation electron cyclotron emission systems on the DIII-D tokamak
journal, October 2010

Rhodes, T. L.; Peebles, W. A.; Nguyen, X.
Review of Scientific Instruments, Vol. 81, Issue 10
DOI: 10.1063/1.3475797

Works referencing / citing this record:

First step toward a synthetic diagnostic for magnetic fluctuation measurements using cross-polarization scattering on DIII-D
journal, October 2018

Wang, G.; Rhodes, T. L.; Crocker, N. A.
Review of Scientific Instruments, Vol. 89, Issue 10
DOI: 10.1063/1.5036791

Intermediate- k density and magnetic field fluctuations during inter-ELM pedestal evolution in MAST
journal, November 2015

Hillesheim, J. C.; Dickinson, D.; Roach, C. M.
Plasma Physics and Controlled Fusion, Vol. 58, Issue 1
DOI: 10.1088/0741-3335/58/1/014020

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Similar Records

Title: Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak

Abstract

Citation Formats

Linear Mode Conversion by Magnetic Fluctuations in Inhomogeneous Magnetized Plasmas journal, April 1989

Electromagnetic wave scattering from magnetic fluctuations in tokamaks journal, March 1992

Doppler reflectometry for the investigation of propagating density perturbations journal, January 2001

Internal Magnetic Turbulence Measurement in Plasma by Cross Polarization Scattering journal, August 1995

Microwave scattering near the cut-off layer by density and magnetic field fluctuations journal, April 1994

Internal magnetic fluctuations and electron heat transport in the Tore Supra tokamak: Observation by cross-polarization scattering journal, June 1998

Measurement of magnetic fluctuations of electromagnetic plasma waves by cross-polarization scattering journal, January 1997

Cross-polarization scattering from low-frequency electromagnetic waves in the GAMMA10 tandem mirror journal, January 1999

Experiments on cross-polarization scattering in the upper hybrid resonance region journal, June 2005

A novel, multichannel, comb-frequency Doppler backscatter system journal, October 2010

Quasioptical design of integrated Doppler backscattering and correlation electron cyclotron emission systems on the DIII-D tokamak journal, October 2010

First step toward a synthetic diagnostic for magnetic fluctuation measurements using cross-polarization scattering on DIII-D journal, October 2018

Intermediate- k density and magnetic field fluctuations during inter-ELM pedestal evolution in MAST journal, November 2015

Linear Mode Conversion by Magnetic Fluctuations in Inhomogeneous Magnetized Plasmas
journal, April 1989

Electromagnetic wave scattering from magnetic fluctuations in tokamaks
journal, March 1992

Doppler reflectometry for the investigation of propagating density perturbations
journal, January 2001

Internal Magnetic Turbulence Measurement in Plasma by Cross Polarization Scattering
journal, August 1995

Microwave scattering near the cut-off layer by density and magnetic field fluctuations
journal, April 1994

Internal magnetic fluctuations and electron heat transport in the Tore Supra tokamak: Observation by cross-polarization scattering
journal, June 1998

Measurement of magnetic fluctuations of electromagnetic plasma waves by cross-polarization scattering
journal, January 1997

Cross-polarization scattering from low-frequency electromagnetic waves in the GAMMA10 tandem mirror
journal, January 1999

Experiments on cross-polarization scattering in the upper hybrid resonance region
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