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arXiv · 0905.0545

Antiproton magnetic moment determined from the HFS of antiprotonic helium

T. Pask·D. Barna·A. Dax·R. S. Hayano·M. Hori·D. Horváth·S. Friedreich·B. Juhász·O. Massiczek·N. Ono·A. Sótér·E. Widmann
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Abstract

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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T. Pask, D. Barna, A. Dax, R. S. Hayano, M. Hori, D. Horváth, S. Friedreich, B. Juhász, O. Massiczek, N. Ono, A. Sótér, E. Widmann. 2009-05-05. Antiproton magnetic moment determined from the HFS of antiprotonic helium. https://doi.org/10.1016/j.physletb.2009.05.038

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