Strong-potential Born-approximation calculations of 1s-2p electron capture.

Abstract

Cross sections for electron capture into the 2p level evaluated with use of the strong potential Born approximation are presented. While these 2p cross sections are smaller than cross sections for capture into the 1s and 2s levels at high velocities, nevertheless the Thomas peak is clearly evident at energies above 1 MeV in both the m=0 and \ensuremath{\Vert}m\ensuremath{\Vert}=1 magnetic substates in atomic hydrogen. At energies above 10 MeV where the Thomas peak is important, cross sections for capture into m=0 and \ensuremath{\Vert}m\ensuremath{\Vert}=1 are comparable. Consequently, the polarization fraction becomes negative at high energies in sharp contrast to Brinkman-Kramers results where the polarization fraction stays near its maximum value.