辐射防护玻璃照射量累积因子的计算及分析

为研究γ放射源操作热室观察窗辐射防护玻璃的累积因子，开展高活度γ放射源热室观察窗的设计，本研究根据五种常用辐射防护玻璃的成分以及ANSI/ANS-6.4.3的数据，得到五种常用辐射防护玻璃的照射量累积因子G-P插值法参数，并利用这些参数计算五种辐射防护玻璃在⁶⁰Co、⁷⁵Se、¹³⁷Cs、¹⁹²Ir核素γ射线照射下的照射量累积因子，拟合得到照射量累积因子随玻璃厚度的变化函数，并与利用等效铅厚度法得到的结果进行比较。结果表明，拟合得到的多项式相关度R²很高；等效铅厚度法仅适用于薄层铅玻璃，在使用铅等效法评价铅玻璃的屏蔽性能时，务必要注意铅玻璃的厚度以及所要屏蔽的γ射线能量。本文计算的辐射防护玻璃照射量累积因子可为热室观察窗的设计及屏蔽性能提供参考。

The Calculation and Fitting of Exposure Buildup Factors for Radiation Protection Glasses

The key to construct the hot-cell is to calculate the buildup factors of radiation-protection glasses. However, there are few reports about the calculation of the buildup factor of radiation-protection glasses. In this article, G-P approximation method coefficients of 5 radiation-protection glasses are calculated according to the chemical composition of radiation-protection glasses and data from ANSI/ANSI-6.4.3. Based on the computed results, buildup factors of these 5 glasses are studied, interpolated and compared with exposure buildup factors calculated by the equivalent thickness of lead for the energy of gamma-ray emitted by nuclides, such as ⁶⁰Co. The results show that the fitting functions of exposure buildup factors and penetration depth have a high relevancy R² for a specific energy, the method of equivalent thickness is only appropriate for thin glasses and special attention must be paid to the glass thickness and gamma-ray energy. The results can be used as reference for the construction and shielding performance assessment of the viewing window of the hot-cell.