RADIATION RESISTANT X-RAY IMAGING IN THE 1 TO 10 KEV ENERGY RANGE

X-RAY IMAGING SYSTEMS (XISS) PROVIDE UNIQUE AND VALUABLE INFORMATION ON PLASMA DYNAMICS. NOTABLY, X-RAY IMAGING OFFERS A CONVENIENT MEANS OF DEFINING SUCH PLASMA PARAMETERSAS TEMPERATURE, DENSITY, AND IMPURITY CONCENTRATION AS A FUNCTION OF POSITION AND TIME WITHIN A MAGNETICALLY CONFINED PLASMA. HOWEVER, X-RAY DETECTORS CAN BE DAMAGED OR DESTROYED BY THE RADIATION ENVIRONMENT ASSOCIATED WITH FUSION EXPERIMENTS. IN ADDITION, SENSITIVE DETECTORS ARE SUBJECT TO VERY HIGH BACKGROUND COUNTING RATES. CONSEQUENTLY, THESE INSTRUMENTS NEED TO BE PROTECTED FROM THE ADVERSE EFFECTS OF THE PLASMA UNDER STUDY. EXISTING X-RAY IMAGING SYSTEMS ARE ILL SUITED TO THE RADIATION ENVIRONMENT OF DT OPERATIONS AT THE TOKAMAK FUSION TEST REACTOR (TFTR), THE COMPACT IGNITION TOKAMAK (CIT), OR FUTURE FUSION REACTORS BECAUSE THERE IS NO EFFECTIVE WAY TO PREVENT UNWANTED RADIATION FROM ENTERING THROUGH THE INSTRUMENT'S APERTURE. X-RAY TRANSMITTING FIBER OPTICS REDUCE THE FLUX OF HARMFUL RADIATION STREAMING THROUGH THE APERTURE OF SUCH AN INSTRUMENT BY SEVERAL ORDERS OF MAGNITUDE. THEREFORE, IT IS POSSIBLE TO DESIGN A SYSTEM THAT IS INSENSITIVE TO THE HIGH RADIATION BACKGROUND. TO PROVE THIS CONCEPT, THIS PROJECT WILL DEVELOP A RADIATION-RESISTANT VERSION OF THE XIS AT TFTR.