Neutron measurement instrumentation development at KIT for the European ITER TBM

Abstract

We present an overview of ongoing work on three types of neutron flux monitors under investigation and development for the two European ITER Test Blanket Modules: 1) a neutron activation system, 2) silicon carbide diodes, 3) selfpowered neutron detectors for fast neutrons. A pneumatic test system for neutronics tests for a TBM-NAS was constructed at the DT neutron generator laboratory of Technical University of Dresden. Several irradiations have been performed with focus on the simultaneous measurement of the extracted activated probes. Furthermore, an engineering assessment in the conceptual design phase has been done which considered issues of design requirements and integration.Within the I_SMART project, KIT is investigating the suitability of an online detector based on silicon carbide semiconductor material and associated electronics for the TBMs. Detectors of several designs have been already irradiated with DT neutrons. Irradiation tests at elevated temperatures have been done and further tests are currently underway.Self-powered neutron detectors (SPND) with novel materials sensitive also to the fast neutron flux expected in the TBMs are under investigation. Simulations with the European Activation System EASY and neutron flux spectra which were calculated with MCNP for the HCPB TBM. Preliminary tests with commercial SPND in a fast reactor were performed. Test detectors are under preparation for testing with DT neutron generators.