Test facility for a neutron flux spectrometer system based on the foil activation technique for neutronics experiments with the ITER TBM

摘要

An important aim of neutronics Test Blanket Module experiments in ITER will be to check the prediction accuracy of nuclear responses in an environment more closely resembling a future fusion reactor than could be achieved so far with existing facilities. Quantities to be measured and checked are for example spectral neutron fluxes, tritium production rates, and nuclear heating. KIT, in cooperation with Technical University of Dresden (TUD), is developing a test measurement system with the goal to allow automated measurements of time profiles of spectral neutron fluxes by means of activation foil packages. The system is currently being installed at the Neutron Laboratory of TUD. In the present state, irradiation in the TBM is simulated with the intensive DT neutron generator of TUD, and a high-purity Ge-Detector is utilized for collecting the gamma-ray spectra of the activated foil packages. The test facility is flexible to explore also other types of gamma-ray detectors such as CdTe or CZT in future investigations which might be found better suited for the final system to be used with the TBM. First test measurements are underway with sets of activation foils which are based on well-established dosimetry reactions while extension to short-living radioisotopes is foreseen for future work.