Title :
"Optical" soft X-ray arrays for fluctuation diagnostics in MFE experiments
Author :
Delgado-Aparicio, L.F. ; Stutman, D. ; Finkenthal, M. ; Tritz, K. ; Moos, H.W. ; Kaita, R. ; Majeski, R.
Author_Institution :
Dept. of Phys. & Astron., Johns Hopkins Univ., Baltimore, MD, USA
Abstract :
Summary form only given. We are developing large pixel count, fast (/spl ges/100 kHz) and continuously sampling soft X-ray (SXR) arrays for the diagnosis of MHD and turbulent fluctuations in MFE experiments. The arrays are based on efficient scintillators, high throughput multi-clad fiber optics, and multi-channel light amplification and integration. Compared to conventional X-ray diode arrays, such systems can provide vastly increased spatial coverage (e.g. 2-D tangential imaging), access to difficult locations and potentially circumvent the neutron damage encountered with typical X-ray diodes. A prototype eight-channel array is being built using columnar CsI:Tl deposited on a fiber optic faceplate as an SXR converter and a multi-anode PMT and APD as photoamplifiers. Columnar CsI:Tl was found to have conversion efficiency superior to that of amorphous depositions. The overall system efficiency is measured using laboratory SXR sources, while the time response and signal-to-noise performance are evaluated by recording MHD activity from the Current Drive Experiment Upgrade (CDX-U) and the National Spherical Torus Experiment (NSTX) at PPPL.
Keywords :
fusion reactor design; fusion reactor instrumentation; plasma diagnostics; plasma diodes; plasma fluctuations; plasma magnetohydrodynamics; plasma turbulence; solid scintillation detectors; 100 kHz; 2D tangential imaging; CDX-U; CsI:Tl; Current Drive Experiment Upgrade; MHD; NSTX; National Spherical Torus Experiment; PPPL; X-ray diodes arrays; amorphous depositions; conversion efficiency; fiber optic faceplate; fluctuation diagnostics; high throughput multiclad fiber optics; magnetic fusion energy experiment; magnetohydrodynamics; multianode PMT; multichannel light amplification; neutron damage; optical soft X-ray arrays; prototype eight-channel array; scintillators; signal-noise performance; turbulent fluctuations; Diodes; Fluctuations; Magnetohydrodynamics; Neutrons; Optical arrays; Optical fibers; Optical imaging; Sampling methods; Throughput; X-ray imaging;
Conference_Titel :
Plasma Science, 2004. ICOPS 2004. IEEE Conference Record - Abstracts. The 31st IEEE International Conference on
Conference_Location :
Baltimore, MD, USA
Print_ISBN :
0-7803-8334-6
DOI :
10.1109/PLASMA.2004.1340141
