For a well selected case of resonant double photoionization in neon, two specific aspects are studied in detail by exploring the shapes of energy- and angle-resolved patterns of the triple-differential cross section (TDCS). One concerns the evolution of TDCS patterns for equal energies of the emitted electrons when crossing the resonance. Here similarities and differences for direct and indirect double photoionization are demonstrated. The other aspect concerns the on-resonance pattern where the photoelectron has the same kinetic energy as the autoionization electron. In contrast to former studies of resonance-affected double photoionization, it is shown here for the first time that in the whole angular range of opposite electron emission the TDCS is strongly affected by interference effects predicted by Vegh and Macek (1994).

Measurements of the neon 2p 4 3 P e , 1 D e and 1 S e triple differential cross section (TDCS) for photoionization under equal energy sharing are presented. The experimental data are found to be well reproduced by a model in which the TDCS is parametrized in terms of the relative magnitudes and phases for the s p and p d continuum channels and an electron correlation factor. Within this model, the final-state continuum wavefunction is formulated with respect to the contributing LS components, which allows an analysis of the effects of their different symmetries upon angular correlation patterns.

The neon 2p4 1Se triple differential cross section (TDCS) of photoionization has been measured under equal energy sharing and displays two additional lobes compared with the related TDCS of helium. A model for the TDCS is derived which parameterizes the relative magnitudes and phases for the epsilon S epsilon p and epsilon p epsilon d continuum channels in addition to an electron correlation factor and reproduces the experimental data very well. This model traces the appearance of these additional lobes to the existence and interference of two continuum channels in the final state wavefunction. The present measurement serves as a test case for the more complicated treatment of energy- and angle-resolved double photoionization in rare gases other than helium,.

No abstract

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.