This paper describes an experimental setup developed to measure the beta-ray energy spectrum as well as a Geant4 simulation study conducted to characterize the properties of a beta-spectrometer. The beta-spectrometer comprises a multi-wire chamber to generate signals to indicate the incidence of beta rays and a plastic scintillation detector to measure its energy. The coincidence method of the detector signals was used to remove high gamma-ray interference. To evaluate the performance of the developed spectrometer, the energy spectra were measured with the radionuclide sources (¹³⁷Cs and ²⁰⁷Bi) emitting internal conversion electrons and gamma rays. The gamma-ray interference removal rate of the spectrometer using the coincidence method was 99.12 ± 0.09%. To reconstruct the beta spectrum from the measured spectrum, Monte Carlo simulations using the Geant4 toolkit were performed to calculate the coefficient related to the effect of gamma rays. The obtained spectrum confirmed that the energy resolution and intrinsic internal conversion peak detection efficiency of the beta-spectrometer were 10.2% at 1 MeV and 91.6%, respectively.

本文介绍了一种用于测量 β 射线能谱的实验装置，以及用于表征 β 光谱仪特性的 Geant4 模拟研究。β 光谱仪包括一个多线室，用于生成指示 β 射线入射的信号和一个塑料闪烁探测器，用于测量其能量。采用探测器信号重合法去除高伽马射线干扰。为了评估开发的光谱仪的性能，使用放射性核素源（¹³⁷ Cs 和²⁰⁷Bi) 发射内部转换电子和伽马射线。使用符合法的光谱仪的伽马射线干扰去除率为99.12±0.09%。为了从测得的光谱重建β 光谱，使用Geant4 工具包进行蒙特卡罗模拟以计算与伽马射线效应相关的系数。获得的光谱证实，β-光谱仪的能量分辨率和本征内转换峰检测效率在 1 MeV 和 91.6% 时分别为 10.2% 和 91.6%。