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arXiv · 1907.12571

LIght scalars with lepton number to solve the $(g-2)_e$ anomaly

Susan Gardner·Xinshuai Yan
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Abstract

Scalars that carry lepton number can help mediate would-be lepton-number-violating processes, such as neutrinoless double $\beta$ decay or lepton-scattering-mediated nucleon-antinucleon conversion. Here we show that such new scalars can also solve the anomaly in precision determinations of the fine-structure constant $\alpha$ from atom interferometry and from the electron's anomalous magnetic moment, $a_e \equiv (g-2)_e/2$, by reducing $|a_e|$. Study of the phenomenological constraints on these solutions favor a doubly-charged scalar with mass below the GeV scale. Significant constraints arise from the measurement of the parity-violating asymmetry in M{\o}ller scattering, and we consider the implications of the next-generation MOLLER experiment at Jefferson Laboratory and of an improved $a_e$ measurement.

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Susan Gardner, Xinshuai Yan. 2019-07-29. LIght scalars with lepton number to solve the $(g-2)_e$ anomaly. https://doi.org/10.1103/physrevd.102.075016

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