DBS

Contacts: Quinn Pratt, Stephen Storment

Short Description

Multi-channel Doppler back-scattering (DBS) diagnostic analysis

Keywords

DBS, Flow Velocity, Turbulence, Density Fluctuations

Long Description

The OMFIT - DBS module provides an integrated approach to visualizing and analyzing data from the UCLA multi-channel Doppler back-scattering (DBS) diagnostics installed on the DIII-D and MAST(U) tokamaks. Data from both DIII-D V-band systems (one at the 60-deg port, another at the 240-port) along with legacy systems (e.g. W-band, ‘DBS5’) are available for processing. Detailed analysis over a multiple times (usually order ~ 10) is a primary feature of this module. DBS quadrature spectrum fitting is used for Doppler shift calculation. Ray tracing (GENRAY) is used to calculate scattering parameters. DBS outputs include: turbulent wavenumbers, turbulent flow velocity, radial electric field, omega_E. Most module features are also available for the Q and V band DBS systems installed on the MAST(U) tokamak (provided the user has access to CCFE computer systems).

Typical workflows

• Fetch raw DBS data

• DBS spectrum analysis and visualization

• Doppler shift calculation from the DBS quadrature spectrum

• GENRAY setup with EFIT and Profiles

• Run GENRAY with DBS parameters

• Calculate derived quantities and plot

Supported devices

• DIII-D

• MAST

Tutorials

• Google docs tutorial

Relevant publications

• Peebles, W. A., et al. “A novel, multichannel, comb-frequency Doppler backscatter system.” Review of Scientific Instruments 81.10 (2010): 10D902.

• Rhodes, T. L., et al. “Optimized quasi-optical cross-polarization scattering system for the measurement of magnetic turbulence on the DIII-D tokamak.” Review of Scientific Instruments 89.10 (2018): 10H107.

Classes

• omfit_classes.omfit_base.OMFITcollection()

• omfit_classes.omfit_csv.OMFITcsv()

• omfit_classes.omfit_elm.OMFITelm()

• omfit_classes.omfit_eqdsk.OMFITgeqdsk()

• omfit_classes.omfit_genray.OMFITgenray()

• omfit_classes.omfit_google_sheet.OMFITgoogleSheet()

• omfit_classes.omfit_mds.OMFITmdsValue()

• omfit_classes.omfit_mds.OMFITmds()

• omfit_classes.omfit_profiles.OMFITprofiles()

• omfit_classes.omfit_thomson.OMFITthomson()

Contributors

List of contributors sorted by number of lines authored:

23107 Quinn Pratt
  658 Stephen Storment
  123 Clive Michael
   15 Orso Meneghini
    2 Bhavin Patel
    1 Fusion Bot

Submodules

• GENRAY

Users

List of usernames sorted by number of module imports: ashourvana, prattq, ernst, smithsp, hongrongjie, yuguanying, houshman, kobayashi, fernandezp, grierson, krietedm, meneghini, schmitzl