Development of fiber optic radiation monitor using plastic scintillation fibers

We have developed a radiation monitor by using plastic scintillation fibers (PSF), which we call the fiber optic radiation monitor. For wide-area radiation monitoring, the detection part needs to be longer, therefore we have produced a prototype monitor by combining the PSF and the silica fiber for optical propagation. In this paper we first explain the characteristics when silica fiber of 100 m long is connected to the PSF. We found that in this case, the position resolution would drop. In order to determine the cause, we observed the aspects of optical pulse propagation. It was found that the light is transmitted through the silica fiber and is detected at fiber end as single photons, and the resolution deteriorated due to the difference in the propagation path of each of photons. We next explain the prototype fiber optic radiation monitor with a detection length of 20 m and a total length of 60 m, and its performance.