Towards the electron EDM search. Theoretical study of PbF

TL;DR

This paper presents relativistic ab initio calculations of lead monofluoride's electronic states, hyperfine constants, and effective electric field, aiding the search for the electron's electric dipole moment.

Contribution

It provides new theoretical data on PbF's electronic structure and hyperfine parameters, including the effective electric field relevant for EDM experiments.

Findings

Hyperfine constants agree with previous theories.

Effective electric field on electron is 3.3 x 10^{10} V/cm.

Discussion of sign disagreement with recent experiments.

Abstract

We report ab initio relativistic correlation calculations of potential curves and spectroscopic constants for four lowest-lying electronic states of the lead monofluoride. We also calculated parameters of the spin-rotational Hamiltonian for the ground and the first excited states including P,T-odd and P-odd terms. In particular, we have obtained hyperfine constants of the $^{207}$Pb nucleus. For the $^2\Pi_{1/2}$ state $A_\perp=-6859.6$ MHz, $A_\|=9726.9$ MHz and for the A$^2\Sigma^+_{1/2}$ $A_\perp=1720.8$ MHz, $A_\|=3073.3$ MHz. Our values of the ground state hyperfine constants are in good agreement with the previous theoretical studies. We discuss and explain seeming disagreement in the sign of the constant $A_\perp$ with the recent experimental data. The effective electric field on the electron $E_{eff}$, which is important for the planned experiment to search for the electric dipole moment of the electron, is found to be 3.3 * 10^{10} V/cm.