Photo-ionization cross-sections of Ne II, Ne III and Ne IV

Accurate calculations have been made for the photo-ionization cross-sections of the ground states of Ne II (2P0), Ne III (3P) and Ne IV (4S0). The close-coupling approximation is employed in the dipole length formulation, including in each case, all states of the residual ion dominated by the ground configuration and the next excited configuration. Results are presented for the partial and the total cross-sections at various thresholds of ionization. (author)