Physics Feasibility Studies of a Divertor Charge Exchange Recombination Diagnostic for DIII-D
Abstract
A charge exchange recombination (CER) diagnostic is being investigated for obtaining the two-dimensional patterns of plasma flow and ion temperature in the DIII-D divertor. A measurement of V and TI with centimeter resolution is needed to validate fluid flow-based models, such as UEDGE, which will be used to predict divertor parameters in future devices. Because of the high level of thermal CER in the divertor, the noise in this background is anticipated to exceed that of the active signal. To surmount this problem, a divertor CER diagnostic has been proposed which utilizes non-intrinsic, low-Z impurity injection; a 500 Hz-modulated diagnostic neutral beam; and lock-in detection of the active charge exchange signal via digital post processing. Simulation of the active CER signal and measurement on DIII-D of the background signal with impurity pellet injection should provide a realistic appraisal of the diagnostic feasibility.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- October 2003
- Bibcode:
- 2003APS..DPPKP1003B