MATTER AND RADIATION IN THE STRONG MAGNETIC FIELDS OF NEUTRON STARS

Recent observations of the radiation from highly magnetized neutron stars have provided a wealth of information on these objects, but they have also raised many new questions. We study various aspects of the surfaces and magnetospheres of neutron stars, including the cohesive properties and condensation of the stellar surface, formation of magnetosphere acceleration zones, and the initiation and propagation of electron-positron cascades through the magnetosphere. We present calculations of the electronic structure of matter in strong magnetic elds ranging from B = 1012 G to 2 1015 G, appropriate for observed magnetic neutron stars. Our calculations are based on the density functional theory. We nd that condensed matter surfaces composed of hydrogen, helium, and carbon are all bound relative to individual atoms for B = 1012 G or higher. Condensed iron surfaces, however, are only signicantly bound for B> 1014 G. We also present Hartree{Fock calculations of the polarization-dependent photoionization cross sections of the He atom in strong magnetic elds ranging from 1012 G to 1014 G