EMI2, the counting efficiency for electron capture by a KL1L2L3M model Original Research Article

The program EMI2 computes the liquid-scintillation counting efficiency for pure electron capture, single isomeric and electron capture-gamma nuclides. In this second version, the atomic rearrangement process subsequent to electron capture is described in terms of a more sophisticated KL1L2L3M model of 264 different pathways. The addition of Coster–Kronig transitions improves the accuracy of the method, especially for nuclides of low atomic numbers. A Monte Carlo method is applied to simulatethe photoelectric and Compton interactions of X- and γ-photons with the scintillator inside the vial geometry.