Kβ X-ray emission from He-like ions

Relativistic calculations on the energies and electric dipole rates of Kβ X-rays from 1s3p(1P1,3P1)-1s2 (1S0) transitions for He-like ions in the range Z=14-54 are carried out using multi-configuration Dirac-Fock (MCDF) wave functions in the active space interaction approach. The contributions from Breit interaction and quantum electrodynamics have also been included in the calculation. An attempt has been made to find a scaling expression for Breit energy in terms of Zα .The scaled Breit energies are in good agreement with the earlier accurate relativistic results and this ensures the reliability of our scaling procedure. The behavior of MCDF wavefunctions for a given J in the non-relativistic limit has also been studied. The calculated Kβ X-ray energies and rates agree well with other available experimental and theoretical values.