PUB - Publikationen an der Universität Bielefeld

In the first part of this thesis, the transferred spin polarization of resonantly excited Auger electrons of Kr 3d-1 5p photoionized by circularly polarized light was measured. The transferred spin polarization is related to the orientation A10 (and alignment A20) of core holes induced by the primary photoionization process, and to the intrinsic parameters [xi]1 which characterizes the transferred spin polarization of Auger electrons and [alpha]2, the anisotropy parameter which characterizes the angular intensity distribution of Auger electrons. Due to the selection rules of dipole excitation of Kr 3d-1 5p atoms i.e. Ji=1, A10 and A20 are known, [alpha]2 was calculated and measured by Kitajima et al. The calculation of [xi]1 was performed by N. M. Kabachnik and S. Fritzsche. In the second part of this thesis, the spin polarization of Xe 4p near the ionization threshold was measured to examine the calculations of Cherepkov of contribution of the lowest order nondipole term; the electric-dipole-electric-quadrupole interference terms to the spin polarization of Xe np photoelectrons. The quadrupol matrix elements of the np->[epsilon]f transitions in Xe calculated in RPAE have strong maxima near the ionization threshold. This behaviour is similar to the well-known maxima in the dipole nd->[epsilon]f transitions. These dipole nd->[epsilon]f transitions are responsible for the so-called giant resonances in the total photoionization cross section. They are attributed to the double-well shape of the effective potential for the dipole [epsilon]f partial waves. Both the RPAE non-relativistic calculation from Cherepkov and the relativistic IPA adapted calculation from Derevianko agree qualitatively with the measured nondipole component of electron spin polarization.