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Free keywords:
Atom & ion trapping & guiding, Binding energy & masses, Cooling & trapping, Determination of fundamental constants, Trapped ions, A ≤ 5Mass, Mass spectrometry, Penning traps, Atomic, Molecular & Optical, Nuclear Physics
MPINP:
Präzisionsexperimente - Abteilung Blaum
Abstract:
Light-ion trap (LIONTRAP), a high-precision Penning-trap mass spectrometer, was used to determine the atomic mass of 4He. Here, we report a 12 parts-per-trillion measurement of the mass of a 4He2+ ion, m(4He2+)=4.001 506 179 651(48) u. From this, the atomic mass of the neutral atom can be determined without loss of precision: m(4He)=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.