Status of two-dimensional ion velocity measurement system in NSTX
نویسندگان
چکیده
A two-dimensional ion velocity measurement system is being developed under a US-JAPAN collaborative activity. The diagnostic is used to determine Doppler shifts from the intensity ratio of a visible line from the same light source, measured with two interference filters that have different transmission pass bands. A fast visible camera is used as two-dimensional detector. The system was tested using an NSTX He discharge, and images of the plasma in He II light were successfully obtained. The intensity ratio over a 1cm region on the center stack remained almost constant, and the intensity ratio of a 1cm region near plasma edge changed during the discharge. The next step is to get a two-dimensional ion velocity map after the system is calibrated.
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