Saddle-point technique for autoionizing states of the lithium atom. II.De2resonances in the elastic- and inelastic-scattering regions

Abstract

The energy, wave function, oscillator strength, and various radial integrals of the ${}_{}{}^2{}_{}{}^{}D_{}^e{}_{}{}^{}$ resonances of the Li atom are calculated using a saddle-point technique. In the elastic-scattering region, the calculated positions agree excellently with those of accurate experimental measurements for all observed resonances. However, in the energy region between the ${\mathrm{Li}}^{+}$ $1s2s {}_{}{}^3{}_{}{}^{}S$ and $1s2s {}_{}{}^1{}_{}{}^{}S$ thresholds, the agreement with the optical-absorption experiment is comparatively poor. This is reasonable in view of the asymmetry observed in the line shapes, which implies a possible difference between the maximum line intensity and resonance position. A more definitive comparison can only be made if a full scattering calculation is carried out or if the widths and line-profile parameters are measured in the experiment. A tentative assignment is also suggested for the lines observed by Rassi et al. in this energy region. If these assignments are correct, it would mean the present calculation agrees more closely with the scattering experiment than with the optical-absorption experiment between the lowest-two inelastic-scattering thresholds.