Ultraprecise atomic mass measurement of the alpha particle and 4He.
Ultraprecise atomic mass measurement of the alpha particle and 4He.
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α粒子和 4He 的超精密原子质量测量。
DOI：
10.1103/physrevlett.92.220802
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发表时间：
2004
影响因子：
8.6
通讯作者：
P. Schwinberg
中科院分区：
文献类型：
--
作者：
Van Dyck Rs;S. L. Zafonte;S. VanLiew;D. B. Pinegar;P. Schwinberg
α粒子和4 He的原子质量已经通过Penning阱质谱仪测量，该质谱仪利用频移探测器在极其稳定的6.0 T磁场中观察单离子回旋共振。该仪器目前的分辨率接近0.01 ppb [10 ppt（万亿分之一）]，并且主要受到磁体在数百小时观察中的有效稳定性（<5 ppt/h）的限制。领先的系统偏移[在-202（9）ppt处]是由于位于陷阱电极中的图像电荷。α粒子原子质量的新值为4 001 506 179.147（64）nu，4 He质量的相应值为4 002 603 254.153（64）nu（nu=10（-9）u）。16 ppt的不确定度至少比以前的任何测定值小20倍。
The atomic masses of the alpha particle and 4He have been measured by means of a Penning trap mass spectrometer which utilizes a frequency-shift detector to observe single-ion cyclotron resonances in an extremely stable 6.0 T magnetic field. The present resolution of this instrument approaches 0.01 ppb [10 ppt (parts per trillion)] and is limited primarily by the effective stability (<5 ppt/h) of the magnet over hundreds of hours of observation. The leading systematic shift [at -202(9) ppt] is due to the image charge located in the trap electrodes. The new value for the atomic mass of the alpha particle is 4 001 506 179.147(64) nu and the corresponding value for the mass of 4He is 4 002 603 254.153(64) nu (nu=10(-9) u). The 16 ppt uncertainty is at least 20 times smaller than any previous determination.