Research and tests of position sensitive radiation detector

Emoto, Takehiko; not registered  ; Ando, Hideki

From the viewpoint of radiation protection and radiation shielding evaluation, the needs to know the positions that are irradiated by radiation are increasing, because measuring irradiated positions is useful for detecting local streaming at working areas in nuclear facilities and evaluating beam-loss from accelerators. We have investigated and experimented the characteristics of plastic scintillating fiber(PSF), that has been recently developed one of most popular position sensitive particle detectors in high energy physics, for purpose of that we can apply them to the radiation measurements as a position sensitive radiation detector. First, we referred to the results of the committed research performed in last year and to relative works. And, to aim for improvement of efficiency of gamma-ray and for stretch of the detector, we investigated efficiency and resolution of the detectors giving priorities to (a) variation of length and bundle of PSFs hamess, and (b) variation of the irradiated positions. As the results of referring to the works and the experiments on the detectors, we got the followings, (1)The method using the difference of reaching time between the scintillation photons from both ends of PSF is hopeful as position sensitive radiation detecting, because PSF has good time resolution and the time measurements have been recently developed to be rather easy and accurate methods. (2)Position resolution is 20cm to 30cm for collimated gamma-ray of Cs. And, the detectors bundled of ten PSFs have better characteristics of both efficiency and resolution. (3)When the detector is irradiated at near one of the ends, the efficiency and resolution will be 10% to 30% worse than irradiated at middle of it.