ELECTRON CAPTURE INTO EXCITED STATES IN IMPULSE APPROXIMATION

Impulse approximation cross sections are evaluated for the electron capture processes H+ + H(1s) -> H(2p, 3s or 3p) + H+ He 2+ + H(1s) -> He+ (2p or 3s) + H+ The results for capture into the 2p state of atomic hydrogen are in close agreement with the measurements of Stebbings et al. in 1965. Total impulse approximation cross sections for capture by protons and alpha particles are estimated. The proton impact cross sections are practically identical with estimates by Coleman and McDowell based on less reliable data.