Theory of the quasimolecular K-X radiation in the example of the Ni-Ni system

The K-X-ray spectra and anisotropies for the Ni-Ni-system have been calculated for the laboratory energies 30, 60 and 90 MeV. Two-Center-Dirac energies for the three inner shells have been used and the radial, rotational and radiative matrix elements have been calculated. For the radiative matrix elements the long wave-length limit was applied. Coupled channel calculations were used to calculate the ionization amplitudes. It is shown, that within reasonable numerical calculations translation effects can not be incorparated in the radial matrix elements. Therefore radial coupling was neglected. In the calculations shown here, the K-shell was assumed to be empty. The influence of the rotational contribution to spectra and anisotropies has been studied. Comparison with experimental results shows, that the exponential decrease of the spectra is too small for high photon energies. Like in experiment, the calculated anisotropies show a bump close to the Ksub(α)-energy of the united system. (orig.)