Electron Capture Cross Sections of H(2p) Level in the Intermediate Velocity Regime of H+–Na(3s), Na*(3p) Collisions

Abstract

We measured electron capture cross sections of H(2p) level as functions of collision velocity by the observation of Lyman-α line emitted from decaying H(2p) atoms, in H + –Na(3s), and –Na * (3p) collisions. Excited sodium atoms were generated by optical excitation with a tunabe dye-laser and the energy of incident protons was in the range of 1–16 keV. The measured results are consistent with previous experiments if they exist and with theoretical calculations. The characteristic dependences on collision velocity of the cross sections were reproduced by the velocity-matching model in which the characteristics of the intermediate velocity collision were taken into account.