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arXiv · 0801.1134

New Measurement of the Electron Magnetic Moment and the Fine Structure Constant

D. Hanneke·S. Fogwell·G. Gabrielse
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Abstract

A measurement using a one-electron quantum cyclotron gives the electron magnetic moment in Bohr magnetons, g/2 = 1.001 159 652 180 73 (28) [0.28 ppt], with an uncertainty 2.7 and 15 times smaller than for previous measurements in 2006 and 1987. The electron is used as a magnetometer to allow lineshape statistics to accumulate, and its spontaneous emission rate determines the correction for its interaction with a cylindrical trap cavity. The new measurement and QED theory determine the fine structure constant, with alpha^{-1} = 137.035 999 084 (51) [0.37 ppb], and an uncertainty 20 times smaller than for any independent determination of alpha.

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D. Hanneke, S. Fogwell, G. Gabrielse. 2010-03-12. New Measurement of the Electron Magnetic Moment and the Fine Structure Constant. https://doi.org/10.1103/physrevlett.100.120801

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