Measurement of Poloidal Velocity on the National Spherical Torus Experiment

Technical Report · Fri Jun 04 04:00:00 EDT 2010

DOI:https://doi.org/10.2172/981719· OSTI ID:981719

A diagnostic suite has been developed to measure impurity poloidal flow using charge exchange recombination spectroscopy on the National Spherical Torus Experiment. Toroidal and poloidal viewing systems measure all quantities required to determine the radial electric field. Two sets of up/down symmetric poloidal views are used to measure both active emission in the plane of the neutral heating beams and background emission in a radial plane away from the neutral beams. Differential velocity measurements isolate the line-integrated poloidal velocity from apparent flows due to the energy-dependent chargeexchange cross section. Six f/1.8 spectrometers measure 276 spectra to obtain 75 active and 63 background channels every 10 ms. Local measurements from a similar midplane toroidal viewing system are mapped into two dimensions to allow the inversion of poloidal line-integrated measurements to obtain local poloidal velocity profiles. Radial resolution after inversion is 0.6-1.8 cm from the plasma edge to the center.

• Research Organization: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC)
• OSTI ID: 981719
• Report Number(s): PPPL-4525
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CHARGE EXCHANGE
CROSS SECTIONS
DIMENSIONS
ELECTRIC FIELDS
HEATING
NSTX
PLASMA
RECOMBINATION
RESOLUTION
SPECTRA
SPECTROMETERS
SPECTROSCOPY
VELOCITY