Coupled Electron Pair Approximation Calculation of the Electric Dipole Moment of Atomic Yb

The existence of a finite electric dipole moment (EDM) d_a of the closed-shell atom Yb implies parity and time reversal violations involving the nuclear sector. An important effect which can contribute to the Yb EDM is the tensor-pseudotensor electron-nucleus interaction characterized by the coupling constant C_T. Within the Standard Model (SM) of particle physics C_T=0, as this form of interaction is not allowed. If a finite d_a of Yb is observed in experiments, then an estimate of C_T can be obtained by combining with the theoretical calculations. A non-zero C_T implies physics beyond the standard model. In this paper we present the result of our ab initio calculation of the EDM Yb using different many-body methods.