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arXiv · 0708.1786

Bound on the anomalous tbW coupling from two-loop contribution to neutron electric dipole moment

A. Avilez-Lopez·H. Novales-Sanchez·G. Tavares-Velasco·J. J. Toscano
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Abstract

The two-loop contribution to the electric dipole moment (EDM) and the chromo electric dipole moment (CEDM) of an arbitrary fermion f induced by the most general renormalizable tbW coupling with complex left- and right-handed components (a_L and a_R) is calculated. The analytical expressions are numerically evaluated and the current experimental constraints on the electron, neutron and mercury atom EDMs are used to obtain a bound on the complex phase Im(a^*_La_R). It is found that the most stringent constraint, Im(a^*_La_R)<2.33 X 10^{-2}, arises from the neutron EDM.

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A. Avilez-Lopez, H. Novales-Sanchez, G. Tavares-Velasco, J. J. Toscano. 2007-08-13. Bound on the anomalous tbW coupling from two-loop contribution to neutron electric dipole moment. https://doi.org/10.1016/j.physletb.2007.08.012

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