Title: The role of relativistic many-body theory in probing new physics beyond the standard model via the electric dipole moments of diamagnetic atoms,
Abstract: The observation of electric dipole moments (EDMs) in atomic systems due to
parity and time-reversal violating (P,T-odd) interactions can probe new physics
beyond the standard model and also provide insights into the matter-antimatter
asymmetry in the Universe. The EDMs of open-shell atomic systems are sensitive
to the electron EDM and the P,T-odd scalar-pseudoscalar (S-PS) semi-leptonic
interaction, but the dominant contributions to the EDMs of diamagnetic atoms
come from the hadronic and tensor-pseudotensor (T-PT) semi-leptonic
interactions. Several diamagnetic atoms like $^{129}$Xe, $^{171}$Yb,
$^{199}$Hg, $^{223}$Rn, and $^{225}$Ra are candidates for the experimental
search for the possible existence of EDMs, and among these $^{199}$Hg has
yielded the lowest limit till date. The T or CP violating coupling constants of
the aforementioned interactions can be extracted from these measurements by
combining with atomic and nuclear calculations. In this work, we report the
calculations of the EDMs of the above atoms by including both the
electromagnetic and P,T-odd violating interactions simultaneously. These
calculations are performed by employing relativistic many-body methods based on
the random phase approximation (RPA) and the singles and doubles
coupled-cluster (CCSD) method starting with the Dirac-Hartree-Fock (DHF) wave
function in both cases. The differences in the results from both the methods
shed light on the importance of the non-core-polarization electron correlation
effects that are accounted for by the CCSD method. We also determine electric
dipole polarizabilities of these atoms, which have computational similarities
with EDMs and compare them with the available experimental and other
theoretical results to assess the accuracy of our calculations.