Spin-dependent observables in electron-sodium scattering calculated using the coupled-channel optical method

We present coupled-channel optical (CCO) calculations of the elastic and the 3 ${}_{}{}^2{}_{}{}^{}$S–3 ${}_{}{}^2{}_{}{}^{}$P transitions in electron-sodium scattering at 1 to 40 eV. The results are compared with the measurements of spin asymmetries ${\mathit{A}}_{\mathrm{ex}}$, the ratio of final- to initial-spin polarization perpendicular to the scattering plane P’/P, and the angular momentum transferred to the atom perpendicular to the scattering plane for singlet ${\mathit{L}}_{\mathrm{\perp }}^{\mathit{S}}$, triplet ${\mathit{L}}_{\mathrm{\perp }}^{\mathit{T}}$, and spin-averaged ${\mathit{L}}_{\mathrm{\perp }}$. We find excellent agreement with measurements of all of these parameters at all energies. For energies above the ionization threshold we find that inclusion of the continuum target states in the CCO formalism has a very large effect on the spin asymmetries, particularly the 3 ${}_{}{}^2{}_{}{}^{}$P channel, and brings about excellent agreement with experiment. The treatment of the dynamics of the interaction is such that the quality of the structure approximation of the sodium atom may be readily studied.