一种基于蒙卡解析耦合的无源效率刻度方法

目的 将蒙卡模拟与解析计算相结合，建立一种无源效率刻度方法。方法 通过蒙卡模拟对所需型号的探测器进行点对点探测效率计算，建立探测效率网格；从探测效率网格中插值，并使用数值积分方法对常用的点源、圆盘、圆柱、烧杯、球形、U型管、马林杯样品的探测效率进行解析。结果 使用上述耦合方法进行无源效率刻度计算，结果表明：0.2～3 MeV能量范围内的刻度结果与使用蒙卡模拟的刻度结果相对偏差大部分在10%以内，最大相对偏差为18.06%，计算时间缩短了至少86%。应用上述耦合方法对ORTEC公司产的某型号HPGe探测器进行点源无源效率刻度，与实验刻度结果吻合很好，相对偏差均在10%以内。结论 该方法可以推广到HPGe、LaBr₃、NaI等多种探测器的无源效率刻度实际应用中。

A sourceless efficiency calibration method based on the coupling of Monte Carlo simulation and analytical calculation

Objective To establish a sourceless efficiency calibration method by coupling Monte Carlo simulation with analytical calculation. Methods Monte Carlo simulation was used to calculate the point-to-point detection efficiency of specific detectors to establish a detection efficiency grid. The detection efficiency of point source, disc, cylindrical, beaker, spherical, U-tube and Marlin cup samples was analyzed using numerical integration method after detection efficiency grid interpolation.Results The above coupling method was used for sourceless efficiency calibration. Within the energy range of 0.2–3 MeV, the relative deviation of calibration between coupling method and Monte Carlo simulation was mostly less than 10%, the maximum relative deviation was 18.06%, and the computation time was reduced by at least 86%. The above coupling method was used for sourceless efficiency calibration of an HPGe detector manufactured by ORTEC for point source detection, which was in good agreement with the experimental calibration, and the relative deviations were less than 10%.Conclusion This method can be generalized and used in the sourceless efficiency calibration of HPGe, LaBr₃, and NaI detectors.