Modelindependent determinations of the electron EDM and the role of diamagnetic atoms
Abstract
We perform modelindependent analyses extracting limits for the electric dipole moment of the electron and the P,Todd scalarpseudoscalar (SPS) nucleonelectron coupling from the most recent measurements with atoms and molecules. The analysis using paramagnetic systems, only, is improved substantially by the inclusion of the recent measurement on HfF^{+} ions, but complicated by the fact that the corresponding constraints are largely aligned, owing to a general relation between the coefficients for the two contributions. Since this same relation does not hold in diamagnetic systems, it is possible to find atoms that provide essentially orthogonal constraints to those from paramagnetic ones. However, the coefficients are suppressed in closedshell systems and enhancements of P,Todd effects are only prevalent in the presence of hyperfine interactions. We formulate the hyperfineinduced timereversalsymmetry breaking SPS nucleonelectron interaction in general atoms in a mixed perturbative and variational approach, based on electronic Diracwavefunctions including the effects of electron correlations. The method is applied to the Hg atom, yielding the first direct calculation of the coefficient of the SPS nucleonelectron coupling in a diamagnetic system. This results in additionally improved modelindependent limits for both the electron EDM and the nucleonelectron coupling from the global fit. Finally we employ this fit to provide indirect limits for several paramagnetic systems under investigation.
 Publication:

Journal of High Energy Physics
 Pub Date:
 July 2018
 DOI:
 10.1007/JHEP07(2018)012
 arXiv:
 arXiv:1802.02171
 Bibcode:
 2018JHEP...07..012F
 Keywords:

 Beyond Standard Model;
 CP violation;
 High Energy Physics  Phenomenology;
 Physics  Atomic Physics
 EPrint:
 15+5 pages, 6 tables, 1 figure