Development of an ultralow background mass spectrometer for isotope analysis of noble gas atoms using delayed ionization via the metastable state

为降低共振电离质谱用于快堆失效燃料探测定位系统的本底，提出了一种利用亚稳态延迟电离氪、氙同位素的方法。通过使用长波长激光进行延迟电离，可以成功地消除氩和氩二聚体电离对光电子产生的背景的影响，并且与使用短波长紫外激光的常规技术相比，电离效率被评估为约10%。

To reduce background in resonance ionization mass spectrometry applied for the failed fuel detection and location system of fast reactors, we developed a method of delayed ionization of krypton and xenon isotopes via the metastable states. With the use of a long wavelength laser for the delayed ionization, the effect of argon and argon dimer ionization on background generated by photoelectrons could successfully be eliminated, and the ionization efficiency was evaluated to be about 10% compared to that with a conventional technique of using a short-wavelength ultraviolet laser.