Study of Accelerator Mass Spectrometry with a Large Tandem Accelerator

从1992年开始，用大型12UD串联静态加速器研制了加速器质谱（AMS）系统，历时三年。一种“双分子导束法”已经成功地进行了测试，并用于AMS测量，而不需要对现有的串联系统进行任何修改。构建了负离子源系统和粒子检测系统。两个专用于AMS研究的系统都连接到串联系统，并且作为AMS系统的重要组成部分运行良好。到目前为止，已经开始探测到^<14>C,^<26>Al, ^<32>Si, ^<36>Cl元素。结果表明，^<14>的C测量误差在2%以内，灵敏度为3*10^<-15>。这种性能对于使用^<14>C测量的许多研究来说已经足够好了。另一方面，现在对另一种元素的测量精度不高。今后，为了提高重元素的检测精度，我们计划用双分子导束法测量129I，这是一个非常重要的元素，特别是在我们的大型串联加速器上。

An accelerator mass spectrometry (AMS) system has been developed with a large 12UD tandem static accelerator as a three year project starting from 1992.A 'di-molecular pilot beam method' has been tested successfully and is used for AMS measurements without any modification to the existing tandem system.Both a negative ion source system and a particle detection system have been constructed. Both system dedicated on the AMS study are connected to the tandem system and are working very well as a essential parts of the AMS system.Up to now, the detection of ^<14>C,^<26>Al, ^<32>Si, ^<36>Cl elements have been commenced. It is confirmed that ^<14>C measurement can be performed within 2% error and with 3*10^<-15> sensitivity. This performance is good enough for many studies using ^<14>C measurement. On the other hand, the precision of the measurement of another element is not highly now.Hereafter, Adding to an improvement on detection accuracy of the heavier element, we are planning to measure 129I with di-molecular pilot beam method as a very important elements especially on our large tandem accelerator.