大線量被ばく用線量計としてのイメージングプレートの応用開発

抄録

The application of two types of imaging plates (IPs), BAS-MS and BAS-TR, to a passive dosimeter for measuring high-level gamma and X-ray radiation has been attempted. To extend the maximum measurable dose without adapting the readout system, two techniques of using color cellophane and annealing were adopted. These techniques decrease the occurrence of photo-stimulated luminescence (PSL) and reduce exposure levels within the dynamic range of the photomultiplier tube (PMT). The exposure dose can be obtained quickly by the cellophane technique, but it does not account for the effects of fading. Thus, after the cellophane technique is performed, the exposure dose should be confirmed by the annealing technique, which can decrease the effects of fading and give a more precise estimate of quantitative dose. The maximum measurable dose for both the gamma and X-ray extended to over 100Gy using these techniques. The experiment revealed that each upper limit of the dynamic range of BAS-MS and BAS-TR for X-rays was approximately 10Gy and 100Gy, respectively. BAS-TR showed a linearity up to about 200Gy for ⁶⁰Co gamma-rays and up to 10Gy for X-rays.