光刺激發光指環劑量計之劑量演算法研究

Dose algorithm of the finger ring using optically stimulated luminescent dosimeter

吳東曄(Tung-Yeh Wu)

指導教授 ： 許靖涵 ； 許芳裕

國立清華大學/原子科學院/生醫工程與環境科學系/碩士(2012年)

摘要

光刺激發光劑量計(OSLD)將逐漸取代熱發光劑量計(TLD)，可望成為人員劑量計的主流，然而相較於國外的熱潮，國內不論在OSLD的基礎研究或相關應用上都尚在起步階段。本研究提出一套以蒙地卡羅模擬法為基礎的光刺激發光指環劑量計(OSLRD)之劑量演算法，用於解決OSLD之能量依存性所造成的劑量誤判。本演算法亦提出了三種不同角度(0度、30度、60度)為主的劑量修正模式，以降低角度依存性造成的劑量誤差。
本劑量演算法經過核能研究所國家標準實驗室之不同光子能量輻射源的測試驗證，確認本演算法確實可修正能量依存性造成的劑量誤判，整體的劑量誤差約在-11.7至24.5 %。目前國內人員體外劑量評估之認證標準要求為劑量誤差需在±40 %內，本演算法之結果已符合認證要求。

關鍵字

光刺激發光劑量計 ； 熱發光劑量計 ； 指環劑量計 ； 劑量演算法 ； 能量依存性 ； 角度依存性

並列摘要

Optically simulated luminescent dosimeter, OSLD, will take place thermo luminescent dosimeter, TLD, to become the main personal dosimeter. Contrast to international world, the basic OSLD researches and applications in Taiwan are still in the starting-up stage. This study developed a Monte Carlo based dose algorithm for optically simulated luminescent ring dosimeter, OSLRD, to solve the miss-estimated dose value due to energy dependence. This algorithm proposed three models dominated by three angles, such as 0, 30, 60 degree, to modify the error due to angular dependence. The dose algorithm developed in this study had passed the verification performed by the National Standard Laboratory, Institute of Nuclear Energy Research, INER. It was recognized that this algorithm can be used to modify the miss-estimated dose due to energy dependence of OSLD. The overall dose errors in the verification were in the range of -11.7 % to 24.5 %. These results meet the requirements (dose error within ±40 %) of Taiwan Accreditation Foundation, TAF, in the test area of externally personal dose estimation.

並列關鍵字

OSLD ； TLD ； Ring dosimeter ； Dose algorithm ； Energy dependence ； Angular dependence

參考文獻

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