This paper describes the calculation of the response of the most common types of radiation detectors that were used within the first few weeks after the Chernobyl accident to determine the activity of 131I in the thyroids of Belarusian subjects of an epidemiologic study of thyroid cancer. The radiation detectors, which were placed against the necks of the subjects, measured the exposure rates due to the emission of gamma rays resulting from the radioactive decay of 131I in their thyroids. Because of the external and internal radioactive contamination of the monitored subjects, gamma radiation from many radionuclides in various locations contributed to the exposure rates recorded by the detectors. To estimate accurately the contribution from gamma rays emitted from various internal and external parts of the body, the calibration factors of the radiation detectors, expressed in kBq per µR h- 1, were calculated, by means of Monte Carlo simulation, for external irradiation from unit activities of 17 radionuclides located on 19 parts of the body, as well as for internal irradiation from the same 17 radionuclides in the lungs, from caesium radionuclides distributed uniformly in the whole body, and from 131I in the thyroid. The calculations were performed for six body sizes, representative of the age range of the subjects. In a companion paper, the levels of external and internal contamination of the body were estimated for a variety of exposure conditions. The results presented in the two papers were combined to calculate the 131I activities in the thyroids of all 11,732 Belarusian study subjects of an epidemiologic study of thyroid cancer and, in turn, their thyroid doses.

中文翻译：

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切尔诺贝利事故后白俄罗斯进行的身体和衣服的外部和内部放射性污染对甲状腺 131I 测量结果的影响 - 第 2 部分：甲状腺附近探测器响应的蒙特卡罗模拟。

本文描述了切尔诺贝利事故发生后最初几周内使用的最常见辐射探测器类型的响应计算，以确定白俄罗斯甲状腺癌流行病学研究对象甲状腺中 131I 的活性。辐射探测器放置在受试者颈部，测量由于甲状腺中 131I 放射性衰变而发射伽马射线的暴露率。由于受监测对象的外部和内部放射性污染，来自不同地点的许多放射性核素的伽马辐射影响了探测器记录的暴露率。为了准确估计从身体各个内部和外部部分发射的伽马射线的贡献，通过蒙特卡罗模拟的方式计算了辐射探测器的校准因子，以 kBq/μR h- 1 表示，用于外部辐射位于身体 19 个部位的 17 种放射性核素的单位活度，以及来自肺部的相同 17 种放射性核素、均匀分布在全身的铯放射性核素以及甲状腺中的 131I 的内部照射。计算针对代表受试者年龄范围的六种体型进行。在一篇配套论文中，对各种暴露条件下身体的外部和内部污染水平进行了估计。两篇论文中提出的结果相结合，计算出甲状腺癌流行病学研究中所有 11,732 名白俄罗斯研究对象的甲状腺中 131I 活性，以及​​他们的甲状腺剂量。