Calculation of electron–photon coincidence decay of 131mXe and 133mXe including atomic relaxation

Detailed deterministic calculations of electron–photon coincidence spectra for 131mXe and 133mXe, including Auger electrons and X-rays from atomic relaxation, have been performed in order to increase the understanding of observed features in spectra produced by radioxenon measurement systems used in nuclear explosion monitoring. Energies and intensities of Auger electrons and X-rays agree well with earlier calculations, and the predicted intensities and energies for 131mXe show good agreement with observed features in electron spectra. The results can be used in the development of radioxenon calibration and concentration analysis techniques.

► Calculations of the atomic relaxation process in the decay of metastable radioxenon isotopes were performed. ► The calculations were used to simulate electron–photon coincidence spectra obtained in nuclear explosion monitoring. ► The results show good agreement with observed features in measured spectra. ► The results have the potential to be used in future analysis methods for nuclear explosion monitoring.