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A parts-per-billion measurement of the antiproton magnetic moment

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      Abstract

      Precise comparisons of the fundamental properties of matter–antimatter conjugates provide sensitive tests of charge–parity–time (CPT) invariance, which is an important symmetry that rests on basic assumptions of the standard model of particle physics. Experiments on mesons, leptons and baryons have compared different properties of matter–antimatter conjugates with fractional uncertainties at the parts-per-billion level or better. One specific quantity, however, has so far only been known to a fractional uncertainty at the parts-per-million level: the magnetic moment of the antiproton, . The extraordinary difficulty in measuring with high precision is caused by its intrinsic smallness; for example, it is 660 times smaller than the magnetic moment of the positron. Here we report a high-precision measurement of in units of the nuclear magneton μN with a fractional precision of 1.5 parts per billion (68% confidence level). We use a two-particle spectroscopy method in an advanced cryogenic multi-Penning trap system. Our result  = −2.7928473441(42)μN (where the number in parentheses represents the 68% confidence interval on the last digits of the value) improves the precision of the previous best measurement by a factor of approximately 350. The measured value is consistent with the proton magnetic moment, μp = 2.792847350(9)μN, and is in agreement with CPT invariance. Consequently, this measurement constrains the magnitude of certain CPT-violating effects to below 1.8 × 10−24 gigaelectronvolts, and a possible splitting of the proton–antiproton magnetic moments by CPT-odd dimension-five interactions to below 6 × 10−12 Bohr magnetons.

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      Most cited references 36

      • Record: found
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      Review of Particle Physics

       K.A. Olive (2016)
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        • Record: found
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        Geonium theory: Physics of a single electron or ion in a Penning trap

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          Is Open Access

          Data Tables for Lorentz and CPT Violation

           ,   (2016)
          This work tabulates measured and derived values of coefficients for Lorentz and CPT violation in the Standard-Model Extension. Summary tables are extracted listing maximal attained sensitivities in the matter, photon, neutrino, and gravity sectors. Tables presenting definitions and properties are also compiled.
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            Author and article information

            Journal
            Nature
            Nature
            Springer Nature
            0028-0836
            1476-4687
            October 18 2017
            October 18 2017
            : 550
            : 7676
            : 371-374
            10.1038/nature24048
            © 2017
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