Comparison of calculated (solid line) and experimental (dotted line) Se⁺ PI cross sections. The theoretical curve is a linear combination of the cross sections from the ground configuration (⁴S_3/2, ²D_3/2, ²D_5/2, ²P_1/2, ²P_3/2) weighted by the factors (0.53, 0.15, 0.05, 0.11, 0.16), respectively. The theoretical cross section was convolved with a Gaussian of 28 meV FWHM to reproduce the experimental resolution.