α能谱法测量222Rn/220Rn气体活度浓度过程中的拖尾修正

α能谱法是环境中²²²Rn/²²⁰Rn气体活度浓度测量的重要方法之一。吸收层及探测器能窗等导致的α能谱低能拖尾是影响²²²Rn/²²⁰Rn活度浓度准确测量的重要因素。为修正α能谱法对²²²Rn/²²⁰Rn气体活度浓度的测量结果，本文从原理上探讨了拖尾形成的原因及其对²²²Rn/²²⁰Rn气体活度浓度测量的影响。结合商用测氡仪，实验修正了²²²Rn/²²⁰Rn气体活度浓度的测量结果，对修正前后的结果进行了实验比对。研究表明，经准确刻度后的修正因子和刻度因子能很好地用于修正²²²Rn/²²⁰Rn气体活度浓度的测量结果，保证了测量结果的准确性。建议在对α能谱法测量²²²Rn/²²⁰Rn气体活度浓度的仪器进行刻度检定时，必要情况下需对拖尾修正因子和刻度因子进行适当刻度。

Peak Tailing Correction in Measurement of 222Rn/220Rn Activity Concentration With α Spectrum Method

α spectrum method is one of the most important methods in measurement of ²²²Rn/²²⁰Rn concentration in environment. However, the peak tailing from high energy particles is an obstacle for accurate measurement. To improve the accuracy of measurement, study on the mechanism and effect of the tailing were carried out, and calibrating experiments on peak tailing correction factors were also realized using ERS-2 monitor. The peak tailing correction factors and calibration factors of ²²²Rn/²²⁰Rn were measured by experiment and their accuracy were also tested. It is suggested that during calibrating α spectrum monitor of ²²²Rn/²²⁰Rn activity concentration, the peak tailing correction and calibration factors should be recalibrated if necessary.