Development of wide area detector for the 2012 model of the 6 Li time analyzer neutron detector system

A 2012 model 6Li time analyzer neutron detector (LiTA12) system has been developed as a high-count-rate neutron detector. An exclusive function with a center-of-gravity calculation, which not only prevents over-counting due to cross-talk, but also obtains a fine position resolution, has been included. As a highcount-rate detector, this device can detect neutrons with a 3mm position resolution in a detection area of 5×5 cm2 and is arranged as a 16×16 matrix with a detection efficiency of approximately 40% of that of a 3He detector. A maximum count rate of 50 million counts per second (Mcps) is obtained. Using the exclusive function, the center-of-gravity pixel size obtained is 0.4 mm, although the actual pixel size is 3mm. Furthermore, this function also enables a wide area detector in an area of 10 × 10 cm2 using four multi-anode (8 × 8 matrix) photomultiplier tubes. In this case, the pixel size is 0.8mm, although the actual pixel size is 6 mm.