Development of a new fusion power monitor based on activation of flowing water

A new approach has been proposed for monitoring D–T neutrons in the system using neutron activation of flowing water via the 16O(n,p) 16N reaction. The basic idea of the approach is to utilize the Cherenkov light, which is produced by energetic β-particles from 16N in water, in the vicinity of a neutron source and then transmit the light by an optical fiber to the remote light sensor. Further feasibility studies require development of a water Cherenkov detector with an efficient light collection system that satisfies neutron monitoring requirements. Two different designs of the water Cherenkov detector with a fiber readout, as well as results of their irradiation tests are presented in the paper. Designs and the experimental setup are not yet optimized for best performance; obtained detector parameters demonstrate potential capabilities of the proposed approach.