High-sensitivity reactive desorption measurement by means of metastable atom beams

随着聚变反应堆作为未来能源的技术发展，阐明反应堆壁面上发生的导致氢燃料在反应堆中堆积或保证反应堆耐腐蚀特性的反应是非常重要的。由于反应产物或吸附物种的高灵敏度鉴定是研究中不可或缺的，我们开发了用于脉冲亚稳态原子束的技术，该技术使吸附物的高灵敏度解吸测量成为可能。首先发展了产生长寿命激发态亚稳态原子束的技术，然后引入了由三对N/S磁体组成的六极磁体，以保持高强度。最后，建立了一个利用音叉斩波器的机械斩波系统，用于形成亚稳态脉冲原子束。

Through the technological development of fusion reactors as the future energy resources, it is quite important to elucidate the reactions taking place on the reactor wall surfaces which lead to the inventory of hydrogen fuel in reactors or ensure the corrosion resistant characteristics of reactors. Since the high-sensitivity identification of the reaction products or the adsorbed species is indispensable for the research, we developed technologies for pulsing the metastable atom beams which enabled the high-sensitivity desorption measurement of adsorbates. Firstly, the technology to generate a beam of metastable atoms in their long-lived excited states was developed and then a hexapole magnet consisting of three pairs of N/S magnets cylindrically around an open bore was introduced to deliver the beam keeping at its high intensity. Lastly, a mechanical chopping system using tuning fork choppers was established for forming a pulsed beam of metastable atoms.