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arXiv · 2107.04716

Sub-GeV $U(1)_{R}$ gauge boson to address the proton radius discrepancy

Carlos Alvarado·Alfredo Aranda·Cesar Bonilla
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Abstract

We propose a Standard Model extension by a $U(1)_{R}$ gauge symmetry where only right-handed chiral fermions can carry a non-trivial charge. Here we show that the simplest anomaly-free solution to accommodate the proton charge radius discrepancy takes right-handed muons $\mu_R$ and first generation quarks, $u_R$ and $d_R$. Consistency with the latest muon's $(g-2)$ measurements is achieved through an extra light scalar, which itself must lie in the tens of MeV mass range to be viable.

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Carlos Alvarado, Alfredo Aranda, Cesar Bonilla. 2021-07-09. Sub-GeV $U(1)_{R}$ gauge boson to address the proton radius discrepancy. https://doi.org/10.1103/physrevd.104.115019

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