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DOE OSTI · 1976500

On ( g – 2) μ from gauged $\mathrm{U(1)_X}$

Greljo, Admir·Stangl, Peter·Thomsen, Anders Eller·Zupan, Jure
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Abstract

We investigate an economical explanation for the (g – 2) μ anomaly with a neutral vector boson from a spontaneously broken U(1) X gauge symmetry. The Standard Model fermion content is minimally extended by 3 right-handed neutrinos. Using a battery of complementary constraints, we perform a thorough investigation of the renormalizable, quark flavor-universal, vector-like U(1) X models, allowing for arbitrary kinetic mixing. Out of 419 models with integer charges not greater than ten, only 7 models are viable solutions, describing a narrow region in model space. These are either L μ – L τ or models with a ratio of electron to baryon number close to –2. The key complementary constraints are from the searches for nonstandard neutrino interactions. Furthermore, we comment on the severe challenges to chiral U(1) X solutions and show the severe constraints on a particularly promising such candidate.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSnew gauge interactionsnew light particles

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Greljo, Admir, Stangl, Peter, Thomsen, Anders Eller, Zupan, Jure. 2022-07-15. On ( g – 2) μ from gauged $\mathrm{U(1)_X}$. https://doi.org/10.1007/jhep07(2022)098

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