Application of imaging plate to measurement of radiation contamination and neutron spatial distribution

In this study, we applied an imaging plate (IP) which is a high-sensitive, -resolution and two-dimensional digital radiation sensor to 1) detecting of low-level contamination that was difficult to detect by a conventional way, and 2) to measurement of spatial distributions of thermal and fast neutrons and 3) profile measurement of proton beam intensity in 107 ∼108 cm-2 ·s-1 which is difficult to measure by current and particle measurement. For contamination detection, a large-size IP (20 cm x 40 cm) was disposed to the sample, and the position and intensity of the contamination was identified unambiguously by scanning IP. For neutron measurement, activation foils were combined with IP to avoid γ -rays from neutron sources and radioactive accelerator components. We placed small gold and aluminum activation foils at many points of interest accelerator room, and after irradiation, disposed them on IP as they were irradiated. This method enables to measure neutron spatial distribution in a single scanning. We extended this method to profiling of proton beams with intensity too low to measure by beam current but too strong to pulse counting, by using a thin copper foil