2-D phase contrast imaging of turbulence structure on LHD

Author

Vyacheslavov, Leonid N. ; Tanaka, K. ; Sanin, A.L. ; Kawahata, K. ; Michael, C. ; Akiyama, T.

Author_Institution

Budker Inst. of Nucl. Phys., Novosibirsk, Russia

Volume

33

Issue

2

fYear

2005

fDate

4/1/2005 12:00:00 AM

Firstpage

464

Lastpage

465

Abstract

CO₂ laser-based phase contrast imaging (PCI) equipped with a 6 by 8 element two-dimensional (2-D) array of photoconductors is used on the large helical device (LHD) for studying plasma density microfluctuations. Observing 2-D structures of turbulence and strong magnetic shear along the viewing line on LHD permit conversion of a 2-D-PCI image to a 2-D picture of the radial distribution of the turbulence k-spectrum. The PCI images are sampled at 1 MHz so the images or associated spectral distributions, when assembled in a movie, present the dynamic radial structure of turbulence.

Keywords

plasma density; plasma diagnostics; plasma fluctuations; plasma toroidal confinement; plasma turbulence; stellarators; 1 MHz; 2D PCI image; 2D phase contrast imaging; CO₂ laser-based phase contrast imaging; LHD; large helical device; plasma density microfluctuations; strong magnetic shear; turbulence k-spectrum radial distribution; turbulence structure; two-dimensional photoconductor array; Detectors; Fluctuations; Magnetic analysis; Phased arrays; Plasma density; Plasma measurements; Plasma temperature; Plasma transport processes; Toroidal magnetic fields; Two dimensional displays; Anomalous transport; fusion plasma; magnetic confinement; microturbulence; phase contrast;

fLanguage

English

Journal_Title

Plasma Science, IEEE Transactions on

Publisher

ieee

ISSN

0093-3813

Type

jour

DOI

10.1109/TPS.2005.845955

Filename

1420528