Testing the aμ anomaly in the electron sector through a precise measurement of h/M

The persistent aμ≡(g-2)/2 anomaly in the muon sector could be due to new physics visible in the electron sector through a sub-ppb (parts per 109) measurement of the anomalous magnetic moment of the electron ae. Driven by recent results on the electron mass [S. Sturm, Nature 506, 467 (2014)NATUAS0028-083610.1038/nature13026], we reconsider the sources of uncertainties that limit our knowledge of ae including current advances in atom interferometry. We demonstrate that it is possible to attain the level of precision needed to test aμ in the naive scaling hypothesis on a time scale similar to next-generation g-2 muon experiments at Fermilab and JPARC. In order to achieve this level of precision, knowledge of the quotient h/M, i.e., the ratio between the Planck constant and the mass of the atom employed in the interferometer, will play a crucial role. We identify the most favorable isotopes to achieve an overall relative precision below 10-10. © 2014 American Physical Society.