γ射线康普顿散射的能谱研究

Energy Spectra Investigation of Compton Scattering of γ Ray

利用10 mCi的137Cs放射源发出的662 keV的γ射线,开展了与铝棒材料的康普顿散射实验。在20°～120°散射角度范围,用NaI(Tl)闪烁能谱仪直接测量获得了散射射线的能谱。简要介绍了实验原理和装置,给出了与实验系统配套的探测效率、峰总比等数据,深入讨论了散射射线能谱的特征,获得了散射能量、散射截面与散射角度的关系,并与理论值进行了比较,验证了康普顿散射理论。最后评述了该种康普顿散射能谱测量的方法。

Using the 662 keV gamma ray emitted by 10 mCi L37Cs radioactive source, Compton scattering experi- ment was carried out with the aluminum rod. The spectra of the scattered rays in the scattering angle range of 20°＋ 120° were obtained directly by the NaI（T1） scintillation spectrometer. The experimental principle and device were described briefly. Some related parameters such as the detection efficiency, the peak - to - total ra- tio, were delivered to match with the experimental system. The characteristics of the spectra of scattering ray were analyzed to obtain the dependence of scattering energy and the scattering cross section on the scattering an- gle. The experimental results compared to the theoretical prediction to verify the theory of Compton scattering. This direct measurement of Compton scattering energy spectra was a/so evaluated finally.