Total and partial (4d ', 4f ', 5s ', 5p ', Sd ', 6s ') cross sections of atomic Ba, La, and Ce have been determined by absorption and photoelectron spectroscopy in the range of the giant 4d~(4f, ef) resonances. Many electron theories that take polarization and relaxation effects into account describe the gross features of the spectra but in many cases fail to reproduce the exact energy positions, line shapes, and amplitudes of the resonances in the cross sections of the main and satellite lines.

Excitation and decay of the 4d '(4, e)f giant resonances of atomic Sm, Eu, and Gd have been investigated by photoabsorption and photoelectron spectroscopy. The experimental total and partial cross sections are compared to those predicted by many-electron theories. Autoionization into the 4f 'el continuum dominates. The character of the giant resonances is closer to that of a 4d '4f resonance than to that of a 4d 'ef shape resonance encountered for Ba and La.

The intrinsic linewidths of 2s2p5(1,3P)3s2P and 2s2p5(1,3P)3p2S correlation satellites were determined from high resolution photoelectron spectra. The authors find widths of 0.41(5) eV for the (1P)3p2S satellite and 0.11(4) eV for the (3P)3p2S satellite. This confirms the prediction that the decay of the (1P)3p2S state is dominated by a multiplet Auger transition to the 2s2p5(3P) ionic state. The resulting broadening of the (1P)3p2S line is considerably overestimated by a relaxed single-configuration Hartree-Fock calculation, indicating the presence of strong many-electron interactions. In addition, an identification of several new lines of the conjugate shakeup 2s2p5(1P)ns2P Rydberg series and a measurement of the relative line strengths of the satellite excitations are presented.

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Combining the linearly polarized high-flux photon beam of a dye laser and the synchrotron radiation of a vacuum-ultraviolet undulator, lithium atoms have been aligned and excited to Li 1snln'I' core resonances. The angular distribution of the electrons emitted upon the decay of these resonances strongly depends on their symmetry character. Exploiting this dependence, the symmetry of Li 1snln'I' core resonances has been determined. The results allow for stringent tests of theoretical predictions and demonstrate the great potential of angular-resolved photoelectron spectroscopy on aligned atoms.