The structure of high-Z He-like ions

The current progress of spectroscopic studies of heliumlike systems will be reviewed. Special emphasis will be given to both the groundstate as well as to the excited state investigations. For the heaviest ions, the potential of precision spectroscopy will be outlined and its relevance for atomic structure investigations will be discussed. (orig.)21 refs.SIGLEAvailable from TIB Hannover: RO 801(96-02) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Electron bremsstrahlung in collisions of 223 MeV/u He-like uranium ions with gaseous targets

The bremsstrahlung process in the domain of strong Coulomb fields has been investigated for N_2 and Ar target electrons colliding with He-like uranium ions at 223 MeV/u. The doubly differential cross sections for bremsstrahlung were measured at the laboratory observation angles of 48 , 90 , and 132 . Substantial discrepancies were found between the experimental cross secions and the first order Born approximation calculations. The reported data provide a new testing ground for non-perturbative treatment of the coupling between radiation and matter in the presence of strong fields. (orig.)SIGLEAvailable from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman