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arXiv · 2011.02529

CP violating effects in $^{210}$Fr and prospects for new physics beyond the Standard Model

Nanako Shitara·Nodoka Yamanaka·Bijaya Kumar Sahoo·Toshio Watanabe·Bhanu Pratap Das
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Abstract

We report theoretical results of the electric dipole moment (EDM) of $^{210}$Fr which arises from the interaction of the EDM of an electron with the internal electric field in an atom and the scalar-pseudoscalar electron-nucleus interaction; the two dominant sources of CP violation in this atom. Employing the relativistic coupled-cluster theory, we evaluate the enhancement factors for these two CP violating interactions to an accuracy of about 3% and analyze the contributions of the many-body effects. These two quantities in combination with the projected sensitivity of the $^{210}$Fr EDM experiment provide constraints on new physics beyond the Standard Model. Particularly, we demonstrate that their precise values are necessary to account for the effect of the bottom quark in models in which the Higgs sector is augmented by nonstandard Yukawa interactions such as the two-Higgs doublet model.

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Nanako Shitara, Nodoka Yamanaka, Bijaya Kumar Sahoo, Toshio Watanabe, Bhanu Pratap Das. 2021-02-21. CP violating effects in $^{210}$Fr and prospects for new physics beyond the Standard Model. https://doi.org/10.1007/jhep02(2021)124

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