Antiproton magnetic moment determined from the HFS of antiprotonic helium

Physics Letters B (Impact Factor: 6.13). 05/2009; 678:55-59.
Source: arXiv


We report a determination of the antiproton magnetic moment, measured in a three-body system, independent of previous experiments. We present results from a systematic study of the hyperfine (HF) structure of antiprotonic helium where we have achieved a precision more than a factor of 10 better than our first measurement. A comparison between the experimental results and three-body quantum electrodynamic (QED) calculations leads to a new value for the antiproton magnetic moment is -2.7862 (83) nuclear magnetons, which agrees with the magnetic moment of the proton within 2.9 x 10e-3.

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Available from: Eberhard Widmann, Oct 13, 2015
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