Relative intensities and of Yb by impact of 1.0 - 8.5 MeV ions

The PIXE spectra resulting from ion beam bombardment in the energy range of 1.0 - 8.5 MeV of a thin target of ytterbium were measured to obtain the relative intensity and of L-shell lines. The results are compared with the calculated L-shell line intensities for helium ion impact in the ECPSSR theory. Modifications of the theory for intra-shell coupling were also calculated and compared with the measured intensities. Good agreement between experimental results and theoretical calculations was found for ion energies greater than 4 MeV. Possible reasons for the discrepancies observed at energies less than 4 MeV were discussed in the framework of the L-subshell coupling effect and binding energy corrections in the united-atom modifications of the ECPSSR theory.