Development of 2-d position-sensitive neutron detector with individual readout; Operation test and establishment of detection system by means of neutron beam

Tanaka, Hiroki; Yamagishi, Hideshi; Nakamura, Tatsuya  ; Soyama, Kazuhiko  ; Aizawa, Kazuya  

We have been developing the 2-d position-sensitive neutron detector with individual readout as next-generation-type detector system for neutron scattering experiments using intense pulsed neutron source. The detection system is designed to fulfill the specifications required for each neutron spectrometer, such as a count rate, efficiency, neutron/-ray ratio, a spatial resolution and a size, by using suitable detector heads. The fundamental and imaging performances of the developed system assembled with a Multi-wire proportional counter head were evaluated using a collimated neutron beam. The system worked stably for long hours at the gas pressure of 5 atm with a mixture of 30% CH (0.26 atm He)at gas gain of 450. The spatial resolutions were 1.4, 1.6 mm (FWHM) for a cathode- and a back strip- direction, respectively, considering a beam size. It was also confirmed that the spatial uniformity of the detection efficiency over the whole sensitive detection area was rather good, 8 % deviation from the average with the optimum discrimination level.