Oxygen Metastable X-Ray Emitters

A crystal spectrometer is used to study 6.5-MeV, foil-excited oxygen-beam x rays. The transitions from $\mathrm{}\left(1s\right)\mathrm{} \mathrm{}\left(2p\right)\mathrm{} 2 {}_{}{}^3{}_{}{}^{}P$ to ${\mathrm{}\left(1s\right)\mathrm{}}^{2}1 {}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}$ He-like and from $\mathrm{}\left(1s\right)\mathrm{} \mathrm{}\left(2s\right)\mathrm{} {}_{}{}^4{}_{}{}^{}P_{}^{\circ }{}_{}{}^{}$ to ${\mathrm{}\left(1s\right)\mathrm{}}^2{\mathrm{}\left(2s\right)\mathrm{}}^2{S}_{\frac{1}{2}}$ Li-like oxygen states are observed to have lifetimes of 1.47 ± 0.02 and 1.87 ± 0.1 nsec, respectively. Both decays are observed to have long-lived components. These results are compared to previous lifetime measurements of x-ray emitting and electron-emitting oxygen states.