Semi-hadronic charge-parity violation interaction constants in CsAg, FrLi and FrAg molecules

We present a systematic study of the nucleon-electron tensor-pseudotensor (Ne-TPT) interaction in the francium-silver (FrAg), cesium-silver (CsAg), and francium-lithium (FrLi) molecules which are candidates for next-generation experimental searches for new sources of charge-parity violation. The considered molecules are all amenable to assembly from laser-cooled atoms, with the FrAg molecule previously shown to be the most sensitive to the Schiff moment interaction in this set. Interelectron correlation effects are treated through relativistic general-excitation-rank configuration interaction theory in the framework of the Dirac–Coulomb Hamiltonian. We find in FrAg the Ne-TPT interaction constant to be \(W_T({\text {Fr}}) = 2.57 \pm 0.21 [\left<\Sigma \right>_A \textrm{kHz}]\), considering the Francium atom as target of the measurement. Taking into account nuclear structure in a multi-source interpretation of a measured electric dipole moment, FrAg is found to be an excellent probe of physics beyond the standard model as this system will in addition to its sizeable Ne-TPT interaction constant greatly constrain fundamental parameters such as the semileptonic four-fermion interaction \(C_{\text {lequ}}\) from which nuclear and atomic \(\mathcal{{CP}}\)-violating properties arise.

Nucleon–electron tensorpseudotensor interaction on the Francium target nucleus in the Francium-Silver molecule, where the corresponding Hamiltonian operator is parity- and time-reversal violating. Details of the interaction are explained in the paper body. These interactions give rise to molecular charge-parity violating effects that can be detected by experiments.