小型加速器质谱系统研制及分析技术研究

加速器质谱(AMS)是测量长寿命放射性核素灵敏度最高的分析技术,在环境、地质、考古、物理等领域有着广泛应用。近年来，AMS装置的小型化在国际上得到了很大发展。为了研发小型化AMS装置及其分析技术，中国原子能科学研究院分别自主研制了加速电压为0.2 MV的单极型AMS装置和端电压为0.3 MV的串列型AMS装置。基于研制的单极型AMS装置，成功开展了14C的高效传输和本底排除技术研究，实现了14C的高灵敏测定，14C/12C的测量灵敏度达到2×10–15；利用研制的串列型AMS装置，开展了低能量下129I的气体剥离条件、本底排除和探测方法研究，建立了129I的高效传输和高灵敏测量方法，129I/127I的测量灵敏度为1×10–14。这是国内首次研制成功小型AMS装置，为AMS国产化奠定基础。

Development the Miniaturized AMS System and Its Analysis Technique

Accelerator mass spectrometry(AMS) is the most sensitive analytical technique for measuring long-lived radionuclides, which is widely used in the fields of environment, geology, archaeology and physics. In recent years, the miniaturization of AMS device has been greatly developed in the world. In order to develop miniaturized AMS devices and their analysis technology, China institute of atomic energy has independently developed a single-stage AMS device with an acceleration voltage of 0.2 MV and a tandem AMS device with an terminal voltage of 0.3 MV, respectively. Based on the single-stage AMS device, the high efficiency transport technique and background eliminating method have been developed for 14C measurement, and realized the high sensitivity measurement of 14C. The measurement sensitivity reaches 14C/12C (atomic number ratio)=2×10–15. Using the 0.3 MV tandem AMS device, the gas stripping conditions, background eliminating and detection methods of 129I at low ion energy were systematically studied, and the high efficient transmission and high sensitive measurement methods of 129I were established, the sensitivity is 129I/127I=1×10–14. This is the first time to develop miniaturized AMS devices in China, which lays the foundation for the localization of AMS.