Alpha spectrometry is one of the greatest nuclear techniques for identification and quantification of α-emitters in the environment due to nuclear fuel cycle operations, nuclear materials and geochemical studies or forensic medicine investigations. This study was conducted to re-evaluate and optimize the factors affecting the performance of a multi-chamber alpha spectrometer (EG&G Ortec) used in our laboratory using an aged α-source of ²³²U in equilibrium with its decay products. The results shown that the energy calibration within energy window 4–9 MeV has been done using alpha particle emissions of ²³²U (t_1/2.70.6 y) and its decay products with good linear fitting (R² > 0.999). At a source to detector spacing of 10 mm, the efficiency of the detectors varied between 15 and 20%; while the better resolution (FWHM) was ~36 keV. These values are lower than those warranted when supplied before 20 years. The minimum detectable activity (MDA) of the detectors varies between 0.8 and 3.1 mBq for the chamber in use. The alpha spectrometer was also verified by certified reference samples to measure activity concentration of alpha emitters (e.g., ²³⁸U, ²³²Th, ²²⁶Ra and ²⁴¹Am) with acceptable coefficient of variance (<10%), $\mathrm{\zeta }$-score (<3) and P-test (<25%). As a result, the optimized alpha spectrometer is valid and can be utilized for monitoring and assessment of natural and artificial α-emitters in different environmental compartments.

由于核燃料循环操作、核材料和地球化学研究或法医学调查，α 光谱法是用于识别和量化环境中 α 发射体的最伟大的核技术之一。本研究旨在重新评估和优化影响我们实验室使用的多室 α 光谱仪 (EG&G Ortec) 性能的因素，该光谱仪使用²³² U的老化 α 源与其衰变产物平衡。结果表明，使用²³² U (t _1/2 .70.6 y) 的α 粒子发射及其具有良好线性拟合的衰减产物 (R ² > 0.999）。当源与探测器的间距为 10 毫米时，探测器的效率在 15% 到 20% 之间变化；而更好的分辨率（FWHM）为~36 keV。这些值低于 20 年之前提供的保证值。对于使用中的腔室，检测器的最小可检测活动 (MDA) 在 0.8 到 3.1 mBq 之间变化。α 光谱仪还通过经认证的参考样品验证，以测量具有可接受的方差系数 (<10%)的 α 发射体（例如，²³⁸ U、²³² Th、²²⁶ Ra 和²⁴¹ Am）的活性浓度，$\mathrm{\zeta }$-score (<3) 和P -test (<25%)。因此，优化后的 α 光谱仪是有效的，可用于监测和评估不同环境隔间中的天然和人工 α 发射体。