The threshold effect on the lifetime of relativistically autoionizing metastable states: The doubly excited spectrum of the fictitious Z = 2.05 atom

By analysing the spectrum and the relativistic autoionization probabilities of parts of the spectra of two and three electron atomic systems with the fictitious charge of Z = 2.05, we add further evidence to our previous many-electron interpretation of the recently observed phenomenon of the sudden change of the lifetimes of the Li 4P states just above the Li+ 1s2s 3S threshold. We suggest that relativistic many-electron analyses are necessary for the correct understanding of possible similar threshold phenomena throughout the periodic table. (orig.)