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arXiv · 2311.04048

Penning-Trap Mass Measurement of Helium-4

Sangeetha Sasidharan·Olesia Bezrodnova·Sascha Rau·Wolfgang Quint·Sven Sturm·Klaus Blaum
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Abstract

Light-Ion Trap (LIONTRAP), a high-precision Penning-trap mass spectrometer, was used to determine the atomic mass of $^{4}$He. Here, we report a 12 parts-per-trillion measurement of the mass of a $^{4}$He$^{2+}$ ion, $m(^{4}\text{He}^{2+}$) = $4.001\:506\:179\:651 (48)$ u. From this, the atomic mass of the neutral atom can be determined without loss of precision: $m(^{4}\text{He})$ = $4.002\:603\:254\:653 (48)$ u. This result is slightly more precise than the current CODATA18 literature value but deviates by 6.6 standard deviations. This is a post-peer-review, pre-copy edit version of an article published in PRL. The final version is available online at https://doi.org/10.1103/PhysRevLett.131.093201.

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Sangeetha Sasidharan, Olesia Bezrodnova, Sascha Rau, Wolfgang Quint, Sven Sturm, Klaus Blaum. 2023-11-07. Penning-Trap Mass Measurement of Helium-4. https://doi.org/10.1103/physrevlett.131.093201

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