Ionization Energies of Hydrogen in Magnetic White Dwarfs

The variational principle is used to determine the ionization energy of a hydrogen atom in its ground state, in the presence of magnetic fields of the order of those found in magnetic white dwarfs and some neutron stars. The results are shown to be better than those obtained by using perturbation theory for all fields and significantly better than those of Cohen et al., for fields less than 3 X 1010 gauss. A general procedure for obtaining the energies of higher levels is outlined.