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We study the linewidths in cascade Auger spectra in synchrotron radiation experiments and discuss their dependence on the lifetimes of the discrete states and the experimental conditions. In particular we consider the possibility of manipulating the linewidths of the first step decay by tuning the bandwidth of the incoming photons. This may be used as an identification method in cases where the spectra from different decays are energetically overlapping. As an example we take the cascade process in Xe following the 4d[sub 5/2] → 6p resonant excitation. [ABSTRACT FROM AUTHOR]

Abstract: The effect of electron correlation has been studied in the case of 4p photoionization of atomic cesium. High resolution synchrotron radiation excited photoelectron spectrum of vapour phase Cs has been measured and compared to the theoretical predictions. The multiconfiguration Dirack–Fock method has been applied in the calculations. [Copyright &y& Elsevier]

Neutral Pb clusters in the size range from a few tens of atoms up to ∼100 atoms are studied using synchrotron-based photoelectron spectroscopy. The electronic structure is seen to differ increasingly from that of the solid when the cluster size decreases. The valence band narrows gradually – down to about one fifth of the solid-state band width at the smallest size of few tens of atoms. Simultaneously the Fermi-edge energy shifts further away from the solid value by more than 2 eV. The Pb 5 d core level binding energy also increases and the spectral features broaden and change in shape. The changes observed for the valence and for the 5 d response energies and shapes are discussed in the context of the metal-to-insulator transition observed earlier in Pb clusters below the critical size of 20–30 atoms/cluster. [ABSTRACT FROM AUTHOR]

Abstract: Binding energy shifts between free and solid state atoms for K 2p and Rb 3d photolines have been determined by measuring the vapor and solid state spectra simultaneously in similar experimental conditions applying synchrotron radiation excited photoelectron spectroscopy. This method has the important benefit that the work function is not needed to correct for different reference energy levels, therefore much more accurate values for binding energy shifts are obtained. [Copyright &y& Elsevier]

Abstract: High resolution 4f photoelectron spectra have been measured from Au, Pb, and Bi vapors using synchrotron radiation. New accurate binding energy values are found to deviate more than 0.3eV for Au from the previous results demonstrating the need for new precise values, e.g. for chemical shift and cluster studies. For Bi both atomic and diatomic lines have been observed simultaneously, molecular lines at 0.96eV lower binding energies. Fine structure splitting created by the coupling of the 4f core hole to the open 6p shell has been found to manifest itself in this high resolution experiment as slightly different line widths for 4f spin components. The fine structure has been investigated also theoretically by calculating the 4f photoionization energies, intensities, and lifetimes using the multiconfigurational Dirac–Fock approach. [Copyright &y& Elsevier]

Abstract: A new electron-energy-resolved electron-ion coincidence setup was developed based on the Scienta SES-100 hemispherical electron analyzer and a Wiley–McLaren type ion TOF spectrometer. With this setup, an electron-ion coincidence study of gas-phase acetonitrile () was performed using synchrotron radiation. The fragmentation patterns in coincidence with resonant Auger electrons were recorded, following N 1s core excitations to the molecular orbital of the character. Also the dissociation of doubly charged molecular ions produced after normal Auger decay of N core-hole states was investigated from PEPICO and PEPIPICO maps. Kinetic energy releases in some reactions were determined with the aid of Monte-Carlo modelling. [Copyright &y& Elsevier]