Schweiger Ch, König C M, Crespo López-Urrutia J R, Door M, Dorrer H, Düllmann Ch E, Eliseev S, Filianin P, Huang W, Kromer K, Micke P, Müller M, Renisch D, Rischka A, Schüssler R X, Blaum K
Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.
Institut für Kernchemie, Johannes Gutenberg-Universität Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany.
Rev Sci Instrum. 2019 Dec 1;90(12):123201. doi: 10.1063/1.5128331.
This paper reports on the development and testing of a novel, highly efficient technique for the injection of very rare species into electron beam ion traps (EBITs) for the production of highly charged ions (HCI). It relies on in-trap laser-induced desorption of atoms from a sample brought very close to the electron beam resulting in a very high capture efficiency in the EBIT. We have demonstrated a steady production of HCI of the stable isotope Ho from samples of only 10 atoms (∼300 pg) in charge states up to 45+. HCI of these species can be subsequently extracted for use in other experiments or stored in the trapping volume of the EBIT for spectroscopic measurements. The high efficiency of this technique extends the range of rare isotope HCIs available for high-precision atomic mass and spectroscopic measurements. A first application of this technique is the production of HCI of the synthetic radioisotope Ho for a high-precision measurement of the Q-value of the electron capture in Ho within the "Electron Capture in Holmium" experiment [L. Gastaldo et al., J. Low Temp. Phys. 176, 876-884 (2014); L. Gastaldo et al., Eur. Phys. J.: Spec. Top. 226, 1623-1694 (2017)] (ECHo collaboration) ultimately leading to a measurement of the electron neutrino mass with an uncertainty on the sub electronvolt level.
本文报道了一种用于将极稀有物种注入电子束离子阱（EBIT）以产生高电荷离子（HCI）的新型高效技术的开发与测试。该技术依靠在阱内通过激光诱导使原子从非常靠近电子束的样品上解吸，从而在EBIT中实现非常高的捕获效率。我们已经证明，从仅含10个原子（约300皮克）的样品中能稳定产生稳定同位素钬的高电荷离子，其电荷态高达45 +。这些物种的高电荷离子随后可被提取用于其他实验，或存储在EBIT的捕获空间中用于光谱测量。该技术的高效率扩展了可用于高精度原子质量和光谱测量的稀有同位素高电荷离子的范围。这项技术的首次应用是生产合成放射性同位素钬的高电荷离子，用于在“钬中的电子捕获”实验[L. 加斯塔尔多等人，《低温物理杂志》176, 876 - 884 (2014); L. 加斯塔尔多等人，《欧洲物理杂志：专题》226, 1623 - 1694 (2017)]（ECHo合作项目）中对钬中电子捕获的Q值进行高精度测量，最终实现对电子中微子质量的测量，其不确定度达到亚电子伏特水平。
