Ionization energies along beryllium isoelectronic sequence

摘要

Ionization energies for the ground state of berylliumlike ions with nuclearcharge numbers in the range Z=16-96 are rigorously evaluated. The calculationsmerge the ab initio QED treatment in the first and second orders of theperturbation theory in the fine-structure constant $\alpha$ with the third- andhigher-order electron-correlation contributions evaluated within the Breitapproximation. The nuclear recoil and nuclear polarization effects are takeninto account. The accuracy of the ionization energies obtained has beensignificantly improved in comparison with previous calculations.