RESONANT INELASTIC-SCATTERING OF QUASI-FREE ELECTRONS ON C(5+)(1S)

We report on studies of resonant inelastic scattering of quasifree electrons on C5+. The resolution of the electron spectrometer is sufficient to resolve the energy structure of electrons emitted as a result of decay of doubly excited 3l3l' configurations in C4+. The line energies compare well with theoretical calculations, using the truncated-diagonalization method. Theoretical calculations based on the Hartree-Fock atomic model for the differential cross sections are also presented. The relative strength of these states within the 3l3l' manifold is measured as a function of scattering angle and compared with theory. The agreement is good for several states, but the 3s3d 3D and 3p3d 1F states show large deviations from the Hartree-Fock-model calculations. Good agreement is found between theory and experimental data for the F1 state when the autoionization rate to the ground state calculated with the truncated-diagonalization method is used in the calculations. It is likely that strong correlation effects for the 3D state are not as well treated in the Hartree-Fock model as by the truncated-diagonalization method.