Krypton 4p, 4s, and 3dpartial photoionization cross sections below a photon energy of 260 eV

Abstract

The photoionization of krypton 4p, 4s, and 3d subshells has been studied theoretically from the 4p threshold and experimentally from the 3d threshold up to a photon energy of 260 eV. In converting the measured count rates of the 4p, 4s, and 3d main photoelectron lines into partial cross sections, we have used recent photoion yield measurements to estimate the contribution of multiple-excitation processes to the total photoabsorption cross section. Theoretical partial cross sections and angular asymmetry parameters have been calculated using the multichannel Dirac-Fock method. Eighteen leading single-excitation channels related to the 4p, 4s, 3d, and 3p hole configurations of the final ionic state were included. Relaxation was taken into account by using separately optimized initialand final-state orbitals and by including all the resulting overlap integrals in the transition amplitudes. The relaxation eKect was found to depend strongly on the photon energy in the near-threshold regions. For the 3d subshell the relaxation reduces the 3d cross section by 35 -40% at the maximum, whereas it is less significant for the 4p and 4s cross sections.PACS number(s): 32.80.Fb

Photoelectron angular distribution and linear magnetic dichroism in the4pphotoemission from Rb atoms

“…Note that, in our calculations, we disregard the effect of channel coupling in the continuum. As was demonstrated by Tulkki et al [32] for the 4p photoionization of Kr, which is very close to the present case, the channel coupling can shift the position of the Cooper minimum by several eV. This may improve the agreement between theory and experiment.…”

Interference effect in the dipole and nondipole anisotropy parameters of the Kr4pphotoelectrons in the vicinity of the Kr(3d)−1<

“…This approximation should be good due to the flatness of the measured data which were measured only at those energies where there are no resonances. One can see there is no contradiction between the present estimation and the earlier theoretical calculations [19,20] within the theoretical uncertainties (typically a factor of 2 for absolute cross sections). The difference between the length and the velocity cross sections originates from the used simple wave functions.…”

Angle-resolved energy dependence of the4p4nd(2S1/Berrah1, Farhat2, Langer3 et al. 1997Phys. Rev. A111120View full textAdd to dashboardCite

“…In the case of the 4s main line, the Bezier curve was generated from known values ͑Samson and Gardener ͓41͔, Tulkki et al ͓17͔,Ehresmann et al ͓42͔͒ as well as our measured data. Figure 7 shows the Bezier curve which is represented by the dotted line.…”