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تسجيل مستخدم جديدCombined explanations of $(g-2)_{mu,e}$ and implications for a large muon EDM
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With the long-standing tension between experiment and Standard-Model (SM) prediction in the anomalous magnetic moment of the muon, $a_mu=(g-2)_mu/2$, at the level of 3-4$sigma$, it is natural to ask if there could be a sizable effect in the electric dipole moment (EDM) $d_mu$ as well. In this context it has often been argued that in UV complete models the electron EDM, which is very precisely measured, excludes a large effect in $d_mu$. However, the recently observed 2.5$sigma$ tension in $a_e=(g-2)_e/2$, if confirmed, requires that the muon and electron sectors effectively decouple to avoid constraints from $muto egamma$. We briefly discuss UV complete models that possess such a decoupling, which can be enforced by an Abelian flavor symmetry $L_mu-L_tau$. We show that, in such scenarios, there is no reason to expect a correlation between the electron and muon EDM, so that the latter can be sizable. New limits on $d_mu$ improved by up to two orders of magnitude are expected from the upcoming $(g-2)_mu$ experiments at Fermilab and J-PARC. Beyond, a proposed dedicated muon EDM experiment at PSI could further advance the limit. In this way, future improved measurements of $a_e$, $a_mu$, as well as the fine-structure constant $alpha$ are not only set to provide exciting precision tests of the SM, but, in combination with EDMs, to reveal crucial insights into the flavor structure of physics beyond the SM.
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