Study of exchange excitation in mercury by means of polarized electrons. II. Theory

For pt.I see ibid., vol.9, no.5, p.791 (1976). The 1 S 0 to 3 P excitation of a 'two-electron atom' by polarized incident electrons is analysed in general terms of the scattering amplitudes using density-matrix techniques. Intermediate coupling for the excited atom is included. The expressions obtained can be used to explain the experimental results for the 6 1 S 0 to 6 3 P 1,2 excitation of mercury. Polarization effects are found if a strong spin-orbit interaction within the excited atom, which gives rise to fine-structure splitting, is taken into account during the collision process.