Performance enhancement of YAG:Ce-phosphor scintillator optical fibre radiation sensors with high temporal resolution based on improvements in high sensitivity detection techniques

Abstract

Improvements in the detection accuracy of miniature optical fibre real time X-Ray radiation sensor based on plastic optical fibre coupled with a fast decay time (10s ns) trivalent cerium activated yttrium aluminum garnet Y3Al5O12 (YAG:Ce) scintillator material is reported. The YAG material is tested only in its powder form. The sensor was irradiated on a Siemens Artiste linear accelerator (linac) and tested for their percentage dose depth (PDD) response whilst being immersed in a standard water test tank in the clinic. The accumulated dose during each test was simultaneously recorded using a standard ionization chamber (PTW Semiflex) which allowed direct comparison and calibration of the PDD response as measured using the Optical Fibre Sensor. Initial experimental results corresponding to the PDD are reported and these demonstrate increased accuracy from previously reported data which is primarily achieved through improvement of exposure conditions for the multi-pixel photon counting (MPPC) detector and monitoring of its real time analogue voltage output.