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

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

DOI:https://doi.org/10.1063/1.4887276· OSTI ID:22308624

Peebles, W. A.; Crocker, N. A.; Nguyen, X. ^[1]

---

1. Physics and Astronomy Department, University of California, Los Angeles, California 90098 (United States)

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. CPS data show interesting features related to internal MHD perturbations known as sawteeth that are not observed on density fluctuations.

• OSTI ID: 22308624
• 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
DENSITY
DISTURBANCES
DOUBLET-3 DEVICE
ELECTROMAGNETIC RADIATION
FLUCTUATIONS
MAGNETOHYDRODYNAMICS
PLASMA
PLASMA IMPURITIES
POLARIZATION
SCATTERING
SIGNAL-TO-NOISE RATIO