# The effects of electron correlation and the Breit interaction on one- and two-electron one-photon transitions in double K hole states of He-like ions ($10\!\leq\!Z\!\leq\!47$)

## TL;DR

This study investigates how electron correlation and the Breit interaction influence x-ray transition energies and rates in double K hole states of He-like ions, using relativistic calculations across ions with Z=10 to 47.

## Contribution

It provides a detailed analysis of electron correlation and Breit interaction effects on transition properties in double K hole states of He-like ions, with new relativistic calculations and insights.

## Key findings

- Breit interaction significantly affects transition rates.
- Electron correlation impacts TEOP transition sensitivity.
- Results agree well with previous studies.

## Abstract

The x-ray energies and transition rates associated with single and double electron radiative transitions from the double K hole state $2s2p$ to the $1s2s$ and $1s^{2}$ configurations of 11 He-like ions ($10\!\leq\!Z\!\leq\!47$) are evaluated using the fully relativistic multi-configuration Dirac-Fock method. An appropriate electron correlation model is constructed with the aid of the active space method, which allows the electron correlation effects to be studied efficiently. The contributions of electron correlation and the Breit interaction to the transition properties are analyzed in detail. It is found that the two-electron one-photon (TEOP) transition is correlation sensitive. The Breit interaction and electron correlation both contribute significantly to the radiative transition properties of the double K hole state of He-like ions. Good agreement between the present calculation and previous work is achieved. The calculated data will be helpful to future investigations on double K hole decay processes of He-like ions.