Hartree-Fock calculations for the photoionization of heavy atoms and ions in neutron star magnetic fields

We determine the photoionization cross section in dipole approximation for heavy atoms and ions in neutron star magnetic field strengths. Continuum states are treated in adiabatic approximation in a self-consistent way. Bound states are calculated by solving the Hartree-Fock-Roothaan equations using finite-element and B-spline techniques. The data are of importance for the quantitative interpretation of observed X-ray spectra that originate from the thermal emission of isolated neutron stars. They can serve as input for modelling neutron star atmospheres with regard to chemical composition, magnetic field strength, temperature and redshift.