Observation of strong two-electron--one-photon transitions in few-electron ion

Moto Togawa, Steffen Kühn, Chintan Shah +22

We resonantly excite the $K$ series of O${}^{5+}$ and O${}^{6+}$ up to principal quantum number $n=11$ with monochromatic x rays, producing $K$-shell holes, and observe their relaxatio…