Instrumentation for a multichord motional Stark effect diagnostic in KSTAR

Journal Article · Sat Nov 15 00:00:00 EST 2014 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4891161· OSTI ID:22308614

Ko, J. ^[1]; Jaspers, R. J. E. ^[2]

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1. National Fusion Research Institute, Yuseong, Daejeon 305-333 (Korea, Republic of)
2. Eindhoven University of Technology, 5612 AZ, Eindhoven (Netherlands)

The motional Stark effect (MSE) diagnostic is used to measure the radial magnetic pitch angle profile in neutral beam heated plasmas. This information is used to calculate the safety factor, q, with magnetic equilibrium reconstruction codes such as EFIT. The MSE diagnostic is important during active shaping of the q profile to optimize confinement and stability, and it has become a key diagnostic in high performance tokamaks. A multichord photo-elastic modulator (PEM) based MSE system is being developed for a real-time plasma current profile control in Korea Superconducting Tokamak Advanced Research (KSTAR). The PEM-based approach is a standard method that measures the polarization direction of a single Stark line with narrow tunable bandpass filters. A tangential view of the heating beam provides good spatial resolution of 1–3 cm, which provides an opportunity to install 25 spatial channels spanning the major radius from 1.74 m to 2.84 m. Application of real-time control is a long-term technical goal after commissioning the diagnostic in KSTAR, which is expected in 2015. In this paper, we describe the design of this newly-constructed multichord MSE diagnostic in KSTAR.

• OSTI ID: 22308614
• Journal Information: Review of Scientific Instruments, Vol. 85, Issue 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BEAMS
DESIGN
ELECTRIC CURRENTS
FILTERS
HOT PLASMA
INCLINATION
MEASURING INSTRUMENTS
PLASMA CONFINEMENT
PLASMA INSTABILITY
POLARIZATION
REPUBLIC OF KOREA
SPATIAL RESOLUTION
STARK EFFECT
TOKAMAK DEVICES