We report on cyclotron frequency measurements on trapped 206,207Pb+ ions by means of the non-destructive Fourier-transform ion-cyclotron-resonance technique at room temperature. In a proof-of-principle experiment using a quartz crystal instead of a coil as a resonator, we have alternately carried out cyclotron frequency measurements for 206Pb+ and 207Pb+ with the sideband coupling method to obtain 21 cyclotron-frequency ratios with a statistical uncertainty of 6 × 10-7. The mean frequency ratio R¯ deviates by about 2σ from the value deduced from the masses reported in the latest Atomic Mass Evaluation. We anticipate that this shift is due to the ion-ion interaction between the simultaneously trapped ions (≈100) and will decrease to a negligible level once we reach single-ion sensitivity. The compactness of such a crystal makes this approach promising for direct Penning-trap mass measurements on heavy and superheavy elements.

中文翻译：

---

石英谐振器，用于在最重的离子上进行质谱分析

我们报告了在室温下通过非破坏性傅里叶变换离子回旋共振技术对捕获的 206,207Pb+ 离子进行回旋频率测量。在使用石英晶体代替线圈作为谐振器的原理验证实验中，我们交替使用边带耦合方法对 206Pb+ 和 207Pb+ 进行了回旋频率测量，获得了 21 个回旋频率比，统计不确定度为 6 × 10-7。平均频率比 R¯ 与从最新的原子质量评估中报告的质量推导出的值相差约 2σ。我们预计这种转变是由于同时捕获的离子 (≈100) 之间的离子-离子相互作用造成的，一旦我们达到单离子灵敏度，就会降低到可以忽略不计的水平。