Development of a flat-panel and resistor-type photomultiplier tube system for high position-resolution two-dimensional neutron detector

A flat-panel and resistor-type photomultiplier tube (FRP) system, which is a two-dimensional positionsensitive neutron detector, has been developed. The FRP detector consists of a scintillator, a multi-anode photomultiplier tube (MA-PMT), a resistor network board, and an FRP amplifier and a readout circuit which is similar to that for the old resistor type photomultiplier tube (RPMT) system. Therefore, the FRP system uses the same readout circuit of the RPMT system. Two types of FRP detector are available. One is the FRP4 detector, which consists of four MA-PMTs with a detection area of 10-cm square. The position resolution due to irradiation of neutron beam with approximately 0.5-mm diameter is 1.26mm in the X axis and 1.61mm in the Y axis. The other one is the FRP1, which consists of one MA-PMT with a detection area of 5-cm square. The position resolution due to irradiation of a neutron beam with approximately 0.5-mm diameter is 0.83mm in the X axis and 0.89mm in the Y axis. The FRP detector can be used for high position-resolution and transmission experiments of a compact neutron source. © 2019 The Japan Society of Plasma Science and Nuclear Fusion Research.