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arXiv · 2003.08195

Large long-distance contributions to the electric dipole moments of charged leptons in the standard model

Yasuhiro Yamaguchi·Nodoka Yamanaka
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Abstract

We reevaluate the electric dipole moment (EDM) of charged leptons in the standard model using hadron effective models. We find unexpectedly large EDM generated by the hadron level long-distance effect, $d_e = { 5.8 \times 10^{-40} }$, $d_\mu = { 1.4 \times 10^{-38}}$, and $d_\tau = { -7.3 \times 10^{-38} }$ ecm, with an error bar of 70\%, exceeding the conventionally known four-loop level elementary contribution by several orders of magnitude.

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Yasuhiro Yamaguchi, Nodoka Yamanaka. 2020-03-18. Large long-distance contributions to the electric dipole moments of charged leptons in the standard model. https://doi.org/10.1103/physrevlett.125.241802

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