Beam-Foil Spectroscopy at Low Initial Ion Energies.<i>Radiative lifetimes measurements for Na, Ne, Ar, Kr and Xe</i>

Abstract

The possibility of determining atomic mean-lives of excited levels in heavier atoms by the beam-foil technique using low initial ion energies was investigated with emphasis on correct energy-loss determinations. Cascade corrections are facilitated at low energies, especially for excited states with long lifetimes. The mean-life of the 3p2P01 level in Na I was determined at 50 keV to be 16.2?0.5 ns. A number of mean-lives of excited levels in neutral and ionized neon, argon, krypton, and xenon were measured at ion energies ranging from 50 to 300 keV. The present xenon mean-lives are considerably shorter than reported in previous beam-foil studies.