Determination of metastable component in ion beams by ion neutralization spectrometry

Ion sources produce a certain admixture of metastable ions i.e. those with a lifetime>10-5 sec. In the present work three ion sources - a Nier source, a Colutron plasma source and a dioplasmatron - and Ar+, Kr+ and Xe+ ions were used and the metastables admixture under varying operation conditions determined by the potential emission method. The admixture was calculated from the energy distribution of secondary ions after impact on a defined metal surface. The accuracy is about 25% and the detection limit 0.1%. Finally the results are described by a simple kinetic model of metastable ions production and annihilation. (G.Q.)