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arXiv · 1810.09413

EFT approach to the electron Electric Dipole Moment at the two-loop level

Giuliano Panico·Alex Pomarol·Marc Riembau
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Abstract

The ACME collaboration has recently reported a new bound on the electric dipole moment (EDM) of the electron, $|d_e|< 1.1 \times 10^{-29}\, {\rm e\cdot cm}$ at 90$\%$ confidence level, reaching an unprecedented accuracy level. This can translate into new relevant constraints on theories beyond the SM laying at the TeV scale, even when they contribute to the electron EDM at the two-loop level. We use the EFT approach to classify these corrections, presenting the contributions to the anomalous dimension of the CP-violating dipole operators of the electron up to the two-loop level. Selection rules based on helicity and CP play an important role to simplify this analysis. We use this result to provide new bounds on BSM with leptoquarks, extra Higgs, or constraints in sectors of the MSSM and composite Higgs models. The new ACME bound pushes natural theories significantly more into fine-tune territory, unless they have a way to accidentally preserve CP.

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Giuliano Panico, Alex Pomarol, Marc Riembau. 2018-10-22. EFT approach to the electron Electric Dipole Moment at the two-loop level. https://doi.org/10.1007/jhep04(2019)090

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