Scalar-pseudoscalar interaction in the francium atom

Abstract

Fr atom can be successively used to search for the atomic permanent electric dipole moment (EDM) [Hyperfine Interactions 236, 53 (2015); Journal of Physics: Conference Series 691, 012017 (2016)]. It can be induced by the permanent electron EDM predicted by modern extensions of the standard model to be nonzero at the level accessible by the new generation of EDM experiments. We consider another mechanism of the atomic EDM generation in Fr. This is caused by the scalar-pseudoscalar nucleus-electron neutral current interaction with the dimensionless strength constant, kT,P . Similar to the electron EDM this interaction violates both spatial parity and timereversal symmetries and can also induce permanent atomic EDM. It was shown in [Phys. Rev. D 89, 056006 (2014)] that the scalar-pseudoscalar contribution to the atomic EDM can dominate over the direct contribution from the electron EDM within the standard model. We report highaccuracy combined all-electron and two-step relativistic coupled cluster treatment of the effect from the scalar-pseudoscalar interaction in the Fr atom. Up to the quadruple cluster amplitudes within the the coupled cluster method with single, double, triple, and noniterative quadruple amplitudes, CCSDT(Q), were included in correlation treatment. This calculation is required for the interpretation of the experimental data in terms of kT,P . The resulted EDM of the Fr atom expressed in terms of kT,P is dFr = kT,P · 4.50 · 10 −18 e · cm, where e is the charge of the electron. The value of the ionization potential of the 2 S 1/2 ground state of Fr calculated within the same methods is in very good agreement with the experimental datum.

Enhancement factor for the electric dipole moment of the electron in the BaOH and YbOH molecules

“…In standard coupled cluster applications the virtual space cutoff is usually set at around 30 a.u., at which point saturation of most properties with respect to the correlation space size is reached (in particular when core electrons are excluded from the correlation procedure). However, it was found that inclusion of the high lying virtual orbitals is important for the correlation of the core electrons for parity violating properties [47,62]. We thus set the cutoff of the virtual space to 2000 a.u.…”

Electric dipole moments from CP-violating scalar leptoquark interactions

“…These two quantities cannot be measured, and are instead obtained from sophisticated molecular structure calculations in Refs. [25][26][27][28][29] for ThO and [30][31][32][33] for HfF + . The current values of the frequency are reported in [6,7]: The electron EDM and the NSID interactions arise from new physics beyond the Standard Model (BSM).…”

Enhanced effect of CP -violating nuclear magnetic quadrupole moment in a HfF+ molecule

“…In Refs. [19,50] we suggested to combine the two-step approach and the direct relativistic Dirac-Coulomb(-Gaunt) approach to take advantages of both approaches.…”