Photoionization of the scandium atom. III. Experimental and theoretical spectra from an excited state

We have carried out a relative measurement of the photoionization cross section of the excited Sc (3${\mathit{d}}^3$${)}_3^2$${\mathit{D}}_{3/2}$ state which lies 36 276.63 ${\mathrm{cm}}^{\mathrm{-}1}$ above the ground state. These experimental results are compared with a calculated photoionization cross section. The theoretical cross section was obtained from scattering parameters and dipole matrix elements that were calculated prior to completion of the experiment and were not adjusted after we obtained the experimental data. The calculated cross section thus demonstrates the predictive power of this theoretical method. The observed features are accurately reproduced in a complicated region of the Sc autoionizing spectrum where numerous interacting channels converge to their respective ionization thresholds.