Strong Modification of Radiative Transition Rates due to a Breit-Interaction-Induced Avoided Crossing

TL;DR

This study observes x-ray emissions from specific excited states of B-like tungsten and bismuth ions, revealing that Breit interaction significantly alters radiative transition rates through wavefunction modifications.

Contribution

It provides experimental evidence and relativistic calculations showing Breit interaction's strong impact on radiative transition rates in highly charged ions.

Findings

Transition rates are strongly modified by Breit interaction.

Wavefunctions are significantly altered due to Breit-induced avoided crossing.

Experimental results agree with relativistic calculations.

Abstract

We present the observations of x-rays emitted from the $1s2s^{2}2p_{1/2}2p_{3/2}$ inner shell excited state of B-like W and Bi ions. The relative transition rates are obtained for two dominant radiative transitions to $1s^{2}2s^{2}2p_{1/2}$ and $1s^{2}2s^{2}2p_{3/2}$. The experimental results and the comparison with rigorous relativistic calculations show that the rates of the strong electric dipole allowed $1s^22s^22p$ -- $1s2s^22p^2$ transitions are strongly modified due to a drastic change in the wavefunction caused by the Breit interaction.