Accurate evaluations of the field shift and lowest-order QED correction for the ground 1¹S-states of some light two-electron ions.

Abstract

Mass-dependent and field shift components of the isotopic shift are determined to high accuracy for the ground 1(1)S-states of some light two-electron Li(+), Be(2+), B(3+), and C(4+) ions. To determine the field components of these isotopic shifts we apply the Racah-Rosental-Breit formula. We also determine the lowest order QED corrections to the isotopic shifts for each of these two-electron ions.