高位置分解能な2次元位置敏感型中性子検出器のFRPシステムの開発

抄録

A Flat-panel and Resistor type PMT (FRP) system which is a two-dimensional position-sensitive neutron detector has been developed. The FRP system is a replacement of the RPMT system which has been out of production. The FRP detector consists of a multi-anode PMT (MA-PMT), a resistor network board and an FRP amplifier, and provides similar signals to those of the RPMT detector. Therefore, the FRP system uses the same readout circuit as that of the RPMT system. There are two types of detectors. One is a FRP4 detector which consists of four MA-PMTs with detection area of 7.5 × 7.5 cm². The position resolution by irradiation of neutron beam of about 0.5 mm diameter is 1.26 mm on the X axis and 1.61 mm on the Y axis. The other is a FRP1 which consists of one MA-PMT with detection area of 3.5 × 3.5 cm². The position resolution by irradiation of neutron beam of about 0.5 mm diameter is 0.83 mm on the X axis and 0.89 mm on the Y axis.