Many scientific domains use gamma-ray spectrometry, but non-destructive gamma scanning and gamma emission tomography of radioactive fuel in particular. In the experimental setting, a collimator is frequently employed ...Many scientific domains use gamma-ray spectrometry, but non-destructive gamma scanning and gamma emission tomography of radioactive fuel in particular. In the experimental setting, a collimator is frequently employed to focus on a particular location of interest in the fuel. Predictive models for the transmitted gamma-ray intensity through the collimator are required for both the optimization of instrument design and the planning of measurement campaigns. Gamma-ray transport accuracy is frequently predicted using Monte Carlo radiation transport methods, but using these tools in low-efficiency experimental setups is challenging due to the lengthy computation times needed. This study focused on the full-energy peak intensity that was transmitted through several collimator designs, including rectangle and cylinder. The rate of photons arriving at a detector on the other side of the collimator was calculated for anisotropic source of SNM (U<sub>3</sub>O<sub>8</sub>). Some geometrical assumptions that depended on the source-to-collimator distance and collimator dimensions (length, radius or length, height, and width) were applied to achieve precise findings.展开更多
X光机绝对光子数的测量在X射线计量中有着十分重要的意义,对其进行测量时需先将探测器的能量—道址函数进行刻度。本文使用放射源对HPGe探测器进行能量刻度,得到其能量—道址函数且其线性相关系数R2=0.999 84。论文结合了CT成像技术,对...X光机绝对光子数的测量在X射线计量中有着十分重要的意义,对其进行测量时需先将探测器的能量—道址函数进行刻度。本文使用放射源对HPGe探测器进行能量刻度,得到其能量—道址函数且其线性相关系数R2=0.999 84。论文结合了CT成像技术,对探测器进行平行光束探测效率的MC模拟,使建模更精确。模拟结果显示,探测效率曲线在11.0 ke V处会出现吸收边,是因为Ge元素被激发产生Kα、Kβ特征X射线发生逃逸,未被记录下来形成逃逸峰所致,这与实际实验情况相符。展开更多
文摘Many scientific domains use gamma-ray spectrometry, but non-destructive gamma scanning and gamma emission tomography of radioactive fuel in particular. In the experimental setting, a collimator is frequently employed to focus on a particular location of interest in the fuel. Predictive models for the transmitted gamma-ray intensity through the collimator are required for both the optimization of instrument design and the planning of measurement campaigns. Gamma-ray transport accuracy is frequently predicted using Monte Carlo radiation transport methods, but using these tools in low-efficiency experimental setups is challenging due to the lengthy computation times needed. This study focused on the full-energy peak intensity that was transmitted through several collimator designs, including rectangle and cylinder. The rate of photons arriving at a detector on the other side of the collimator was calculated for anisotropic source of SNM (U<sub>3</sub>O<sub>8</sub>). Some geometrical assumptions that depended on the source-to-collimator distance and collimator dimensions (length, radius or length, height, and width) were applied to achieve precise findings.
文摘X光机绝对光子数的测量在X射线计量中有着十分重要的意义,对其进行测量时需先将探测器的能量—道址函数进行刻度。本文使用放射源对HPGe探测器进行能量刻度,得到其能量—道址函数且其线性相关系数R2=0.999 84。论文结合了CT成像技术,对探测器进行平行光束探测效率的MC模拟,使建模更精确。模拟结果显示,探测效率曲线在11.0 ke V处会出现吸收边,是因为Ge元素被激发产生Kα、Kβ特征X射线发生逃逸,未被记录下来形成逃逸峰所致,这与实际实验情况相符。
