Electron EDM arising from modulus τ in the supersymmetric modular invariant flavor models

• Published in: The journal of high energy physics Vol. 2021; no. 10; pp. 1 - 36
• Main Authors: Tanimoto, Morimitsu, Yamamoto, Kei
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 22-10-2021; Springer Nature B.V; SpringerOpen
• Subjects: Beyond Standard Model; Breaking; Classical and Quantum Gravitation; Compactification and String Models; CP violation; Decay rate; Dipole moments; Electric dipoles; Electrons; Elementary Particles; Flavor (particle physics); High energy physics; Invariants; Leptons; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Quarks; Regular Article - Theoretical Physics; Relativity Theory; String Theory; Supersymmetric Standard Model; Supersymmetry; Symmetry; Upper bounds; Compactification and String Models; Supersymmetric Standard Model; Beyond Standard Model; CP violation
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP10(2021)183

A
bstract
The electric dipole moment (EDM) of electron is studied in the supersymmetric A4 modular invariant theory of flavors with CP invariance. The CP symmetry of the lepton sector is broken by fixing the modulus
τ
. Lepton mass matrices are completely consistent with observed lepton masses and mixing angles in our model. In this framework, a fixed
τ
also causes the CP violation in the soft SUSY breaking terms. The electron EDM arises from the CP non-conserved soft SUSY breaking terms. The experimental upper bound of the electron EDM excludes the SUSY mass scale below 4–6 TeV depending on five cases of the lepton mass matrices. In order to see the effect of CP phase of the modulus
τ
, we examine the correlation between the electron EDM and the decay rate of the
μ → eγ
decay, which is also predicted by the soft SUSY breaking terms. The correlations are clearly predicted in contrast to models of the conventional flavor symmetry. The branching ratio is approximately proportional to the square of |
d
e
/
e
|. The SUSY mass scale will be constrained by the future sensitivity of the electron EDM, |
d
e
/
e
| ≃ 10
−
30
cm. Indeed, it could probe the SUSY mass range of 10–20 TeV in our model. Thus, the electron EDM provides a severe test of the CP violation via the modulus
τ
in the supersymmetric modular invariant theory of flavors.