Charge-Changing Collisions of 0.7–2.0 MeV Helium Beams in Various Gases. I. Electron Capture

The single and double electron capture cross sections σ 10 , σ 21 and σ 20 of heliumions have been measured in target gases of H 2 , He, N 2 , O 2 , CO 2 , CH 4 , C 2 H 6 and C 3 H 8 in the energy range from 0.7 to 2.0 MeV. The measured cross sections are compared with other experimental and theoretical values for the target gases of H 2 , He, N 2 and O 2 . The additive rule for the charge-changing process of helium ions has been verified by using the cross sections for the carbon-containing molecules. Capture cross sections of helium ions in the collisions with carbon atoms have been estimated.