Theoretical seminar | 09 March 2022

NRC «Kurchatov Institute» - PNPI & Saint Petersburg University
Use of molecules to search for new physics and study nuclear properties

The nonzero value of the permanent electric dipole moment of the electron (eEDM) implies the manifestation of interactions that are nonsymmetric with respect to both spatial parity (P) and time-reversal (T) operations, P,T-violating interactions. The observation of the eEDM at a level significantly bigger than 10^-38 e*cm would indicate the presence of a new physics beyond the standard model of elementary particles; popular extensions of the standard model predict the magnitude of eEDM at the level of 10^-26 – 10^-30 e*cm. Small heavy-atom molecules are very promising systems for such experiments. In the systems, one can achieve a strong effective electric field (Eeff) acting on eEDM that leads to the enhanced effect. However, the interpretation of the experiments in terms of eEDM requires accurate knowledge of the Eeff value, which cannot be measured, and is the task for relativistic quantum chemistry. We have achieved a very high level of predictions of Eeff and related characteristics. Such predictions connect experimental observations with the fundamental properties of the electron and nucleus. In the talk, the present status of experiments and corresponding theoretical developments to search for the electron EDM will be outlined and prospects to improve these findings will be briefly reviewed. Also, related problems to searching for other symmetry violating effects and nuclear properties will be mentioned.

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