Calculation of the parity and time reversal violating interaction in ^{225}RaO

TL;DR

This study calculates the P,T-odd interaction parameter in RaO using relativistic coupled cluster methods, providing results relevant for experiments probing fundamental symmetry violations in ^{225}Ra.

Contribution

The paper introduces a detailed relativistic computational approach to evaluate the P,T-odd parameter in RaO, a novel calculation for this molecule.

Findings

The P,T-odd parameter X in ^{225}RaO is approximately -7532.

The calculated value is close in magnitude to that in ^{205}TlF but with opposite sign.

Results support the potential of RaO for experimental searches of Schiff moments.

Abstract

The 10-electron generalized relativistic effective core potential and the corresponding correlation spin-orbital basis sets are generated for the Ra atom and the relativistic coupled cluster calculations for the RaO molecule are performed. The main goal of the study is to evaluate the P,T-odd parameter X characterized by the molecular electronic structure and corresponding to a "volume effect" in the interaction of the ^{225}Ra nucleus Schiff moment with electronic shells of RaO. Our final result for X(^{225}RaO) is -7532 which is surprisingly close to that in ^{205}TlF but has different sign. The obtained results are discussed and the quality of the calculations is analyzed. The value is of interest for a proposed experiment on RaO [PRA 77, 024501 (2008)] due to a very large expected Schiff moment of the ^{225}Ra nucleus.