Conceptual design of radio isotope production module and application for neutron measurement in A-FNS

Abstract Conceptual design of the Radio Isotope Production Module (RIPM) in Advanced Fusion Neutron Source (A-FNS) is conducted especially by taking horizontal transfer of irradiation samples from a lateral access cell into consideration. Neutron measurements are also planned to be performed with the RIPM by replacing the samples with activation foils. A method with combination of two kinds of foils is proposed for the measurement of distribution of neutrons produced at the lithium target in A-FNS. One is a small foil to accurately measure an absolute value of a reaction rate by using a HPGe detector and the other is a large one to measure its relative spatial distribution by using an imaging plate. The ratio of contribution from product nuclei of a dosimetry nuclear reaction to others is important because the imaging plate is usually unable to discriminate energies of γ-rays. The ratio was investigated for cooling time by using the MCNP and FISPACT codes. It was clarified that the spatial distributions of reaction rates can be monitored with good accuracy over 90% for 209Bi(n,4n)206Bi, 209Bi(n,3n)207Bi, 93Nb(n,2n)92mNb, 27Al(n,α)24Na, and 115In(n,n’)115mIn reactions.