Charge transfer and excitation in slow proton collisions with sodium

The charge transfer and excitation cross sections for protons colliding with Na(3s) atoms are calculated in the incident energy region from 1.7 eV to 5 keV by a quantum-mechanical molecular-orbital close-coupling (QMOCC) method and from 1 to 100 keV by a two-center atomic-orbital close-coupling method. The present QMOCC charge transfer cross section for low energy (<40 eV) is in agreement with some other calculations, but disagrees with the experimental measurements [Z. Phys. A 313, 155, 1983]. For the higher energies, the cross sections calculated by the two methods are in harmony with the experimental and other theoretical data.