We like to thank Horst Drechsel, Uli Heber, and Klaus Werner for helpful discussions and Jochen L. Deetjen for assistance with calculation of the iron-group cross sections. This research was supported by the DLR under grant 50 OR 9705 5. Computations were carried out on CRAY computers of the Rechenzentrum der Universität Kiel. This research has made use of the SIMBAD Astronomical Database, operated at CDS, Strasbourg, France, and of the NIST atomic spectra database.
© European Southern Observatory (ESO) 2000
Online publication: April 10, 2000