Dose Recalculation and Measurement of MicrosSelectron-HDR 192Ir Source

MicroSelectron-HDR銥192射源的劑量再計算與測量

謝煥鈞(Huan-Chun Hsieh) ； 張寶樹(Pao-Shu Chang) ； 郭銘彬(Ming-Pin Kuo) ； 連熙隆(Shi-Long Lian)

《醫護科技學刊》 4卷4期 (2002/10) Pp. 305-311

https://doi.org/10.6563/TJHS.2002.4(4).3

摘要

目的：由於銥192有複雜的γ能譜，所以再計算一個標準包裝的microSelectron-HDR銥192射源之空氣克馬率常數Γδ。用已校正的TLD- 700氟化鋰(LiF)晶片來測量上述射源之空氣克馬。比較劑量的再計算值與測量值。結果亦可應用於新購銥192射源的活度修正。
材料與方法：重新查閱銥192的同位素表之數據後，再計算其空氣克馬率常數Γδ。用銫137射源校正的TLD-700 LiF晶片來測量上述射源之空氣克馬。
結果：對於一個標準包裝的microSelectron-HDR欽192射源而言，考慮0.25 mm厚的不鏽鋼對γ射線所造成的衰滅，空氣克馬率常數Γδ為2.944*10-17Gy m2s-1Bq-1。利用TLD700 LiF晶片來測量10居里(Ci) microSelectron-HDR銥192射源之空氣克馬，所得的結果與再計算的Γδ值相比較。
結論：對於一個新的銥192射源而言，Γδ的再計算值與microSelectron-HDR銥192射源的空氣克馬測量值之間的差異是很有用的。

關鍵字

空氧克馬率常數Γδ ； 銥192射源 ； TLD-700氟化鋰 ； LiF

並列摘要

Purpose: Due to the complex γ- ray spectrum branchings of 192Ir, the air - kerma rate constant Γδor a standard packaged microSelectron-HDR 192Ir source was recalculated. The calibrated TLD-700 LiF chips were used to measure the air-kerma of the above mentioned source. The results of dose recalculation and measurement were compared. The results could be applied in activity correction for a new 192Ir source.
Materials and Methods: After reviewing table of isotope data for 192Ir, the air-kerma rate constant Γδwas recalculated. TLD-700 LiF chips calibrated with a standard 137Cs source were applied in the air-kerma measurement of the source mentioned above.
Results: For a standard packaged microSelectron-HDR 192Ir source, taking into account attenuation of γrays in 0.25 mm stainless steel, the air-kerma rate constant Γδ was obtained as 2.944*10-17Gy m2s-1Bq-1. Results of air-kerma measurement
using TLD-700 LiF chips for a 10 Ci microSelectron-HDR192Ir source was compared with theΓδ recalculation.
Conclusion: The difference betweenΓδ recalculation and air-kerma measurement for microSelectron-HDR192Ir is useful in the activity calibration of a new 192Ir source.

並列關鍵字

air-kerma rate constant Γδ ； 192Ir source ； TLD-700 LiF

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