Electron electric dipole moment and electroweak baryogenesis in a complex singlet extension of the Standard Model with degenerate scalars

Chikako Idegawa; Eibun Senaha

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arXiv · 2309.09430

Electron electric dipole moment and electroweak baryogenesis in a complex singlet extension of the Standard Model with degenerate scalars

Chikako Idegawa·Eibun Senaha

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Abstract

We study the possibility of electroweak baryogenesis in the standard model with a complex scalar field, focusing mainly on a degenerate scalar scenario. In our setup, CP violation is provided by dimensional-5 Yukawa interactions involving the complex scalar field. In contrast to previous studies in the literature, we exemplify a case in which a complex phase in the singlet scalar potential is transmitted to the fermion sector via the higher-dimensional operators and drives BAU. We point out that an electric dipole moment of the electron can be suppressed due to the Higgs mass degeneracy and the presence of a new electron Yukawa coupling. Thus, viable parameter space for electroweak baryogenesis is still wide open for the latest experimental bound set by the JILA Collaboration.

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Chikako Idegawa, Eibun Senaha. 2023-09-18. Electron electric dipole moment and electroweak baryogenesis in a complex singlet extension of the Standard Model with degenerate scalars. https://arxiv.org/abs/2309.09430

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