Miri Hakimabad Hashem, Panjeh Hamed, Vejdani-Noghreiyan Alireza
Mashhad, Iran.
Appl Radiat Isot. 2007 Aug;65(8):918-26. doi: 10.1016/j.apradiso.2007.03.014. Epub 2007 Mar 28.
Response functions of the 3 x 3 in NaI detector, which is mainly used in PGNAA applications, have been calculated by using MCNP-4C code. Calculated results are compared with measured data by using standard gamma-ray sources and prompt gamma-rays from pure element samples to check their accuracy. Prompt gamma-rays from pure element samples were used for this determination in the range from 1.942 to 10.829 MeV by use of (241)Am-Be neutron source and gamma-rays from radioisotope sources were used in the range from 0.081 to 4.438 MeV. Through the precise modeling of the detector structure, the agreement between both results has been improved. A surprising result is that in the PGNAA method the agreement between the MCNP simulation and experiment will be better by using a suitable neutron shield for NaI detector in order to prevent the activation of NaI (Tl) and a proper gamma-shield to attenuate the high-rate 4.438 MeV gamma-ray, (241)Am-Be gamma-ray component.
主要用于脉冲快中子活化分析（PGNAA）应用的3×3碘化钠探测器的响应函数，已通过使用MCNP - 4C代码进行计算。通过使用标准伽马射线源和来自纯元素样品的瞬发伽马射线将计算结果与测量数据进行比较，以检验其准确性。利用（241）Am - Be中子源，在1.942至10.829 MeV范围内使用来自纯元素样品的瞬发伽马射线进行此测定，在0.081至4.438 MeV范围内使用来自放射性同位素源的伽马射线。通过对探测器结构进行精确建模，两者结果之间的一致性得到了改善。一个令人惊讶的结果是，在PGNAA方法中，通过为碘化钠探测器使用合适的中子屏蔽以防止碘化钠（铊）活化，并使用适当的伽马屏蔽来衰减高速率的4.438 MeV伽马射线、（241）Am - Be伽马射线成分，MCNP模拟与实验之间的一致性会更好。
Zotero 插件