Electron capture into excited s states in the target continuum distorted-wave approximation

Total cross sections for electron capture by protons into the ground and excited s states of a hydrogen atom are calculated employing the target continuum distorted-wave approximation. This apparently high-energy approximation, which is much simpler than any other calculation of its kind, is found to be capable of giving good results at energies as low as 50 keV by comparison with other calculations. The authors' calculated total cross sections for capture into 3s and 4s states provide a fair comparison with the experiment of Brower and Pipkin (1989) around 100 keV. Even for the more probable 1s-1s capture the results are in close agreement with existing results. They also present total cross sections for electron capture by protons into various s states from the inner shells of Ne and Ar.