EUV emission spectra in collisions of highly charged tantalum ions with nitrogen and oxygen molecules

Abstract We have performed ion beam collision experiments using multiply charged tantalum ions and observed EUV (extreme ultra-violet) emission spectra in collisions of ions with molecular targets, N 2 and O 2 . Broad UTAs (un-resolved transition arrays) from multiply charged Ta ions were observed, and the mean wavelengths of the UTAs shifted and became shorter at higher charge statea of Ta ions. These UTAs may be attributed to the 4f–5d and 4f–5g transitions. Not only the UTA emission from incident ions, but also the sharp emission lines from multiply charged fragment atomic ions were observed. Production of temporary highly charged molecular ions, their kinetic energy and fragmentation processes have been investigated with coincident detection technique. However, the observation of emission from the fragments might be for the first time. The formation mechanisms of the multiply charged fragment atomic ions from target molecules are discussed.