γ射线探测器能量响应标定技术

Technique of Calibrating Energy Response of γ-ray Detector

叙述了γ射线探测器能量响应的标定原理和方法，即利用Compton散射将强^60Co源的1．25MeV γ射线转换为0．36～1．02MeV（25°～90°）范围内任意能量的系列单能γ射线；采用辐射屏蔽技术和提高能量分辨率方法对7射线探测器进行了该能区的能量响应标定；通过MCNP程序对探测器的能量沉积趋势和不同散射角散射7射线的能量分布进行模拟计算。结果表明：该标定系统信噪比达到了20：1左右，能量分辨率约为6％，0.66MeV的灵敏度与标准^137Cs源直照标定的灵敏度基本一致。

The paper introduces a method and principle for calibrating energy response of γ-ray detector. The energy response may be obtained by means of transforming γ-ray from ^60Co into a series of mono-energetic γ-ray in the range of 0.36～1.02 MeV, shielding radiation-interference and improving energy resolution. The energy distributions of scattered γ-ray at different angles and corresponding energy deposited in detector were simulated by MCNP code. The results show that the signal-to-noise of the system is about 20 ： 1, the energy resolution is about 6%, and the sensitivity of detector to 0.66 MeV γ-ray is in agreement with the one to the γ-ray from ^137Cs.