Electron-loss cross-section measurement of 3He ions by the attenuation method

Abstract We have measured single-electron loss cross sections of 3 He 1+ ions for various solid targets such as C, Al, V, Cr, Cu, Ge, Nb, Ag, Sn and Au at 72 MeV by using the attenuation method. In this method residual 3 He 1+ fractions after charge-changing collisions were measured with a 3 He 1+ incident beam. Concentrations of contaminating atoms in the target were determined by an independent RBS measurement. It was found that surfaces of almost all the targets were covered with thin oxygen layers by which 3 He 1+ fractions were reduced by about 10%. Corrections of the observed loss cross sections are made for the surface oxygen layers.