Electron Capture from Atomic Hydrogen by Protons

Abstract

In a paper by Bates and Dalgarno the BK (Brinkman-Kramers) cross sections together with the groundstate cross section of Jackson and Schiff were used to estimate the Born cross sections for capture into excited states of the hydrogen atom. In the present paper the Born cross sections are calculated numerically for capture into seven different final states. These results show that the estimates of Bates and Dalgarno are very good. In addition, the Born and BK cross sections for capture from $\mathrm{He}\left(1\mathrm{}{s}^2\right)$ are compared with the corresponding quantities for capture from atomic hydrogen. The similarity of certain cross-section ratios for these two atoms suggests the possible use of these ratios to estimate the Born capture cross sections for other atoms from the BK cross sections for the corresponding atoms.