  The availability of the unprecedented spectral resolution provided by modern
X-ray observatories is opening up new areas for study involving the coupled
formation of the continuum emission and the cyclotron absorption features in
accretion-powered X-ray pulsar spectra. Previous research focusing on the
dynamics and the associated formation of the observed spectra has largely been
confined to the single-fluid model, in which the super-Eddington luminosity
inside the column decelerates the flow to rest at the stellar surface, while
the dynamical effect of gas pressure is ignored. In a companion paper, we have
presented a detailed analysis of the hydrodynamic and thermodynamic structure
of the accretion column obtained using a new self-consistent model that
includes the effects of both gas and radiation pressure. In this paper, we
explore the formation of the associated X-ray spectra using a rigorous photon
transport equation that is consistent with the hydrodynamic and thermodynamic
structure of the column. We use the new model to obtain phase-averaged spectra
and partially-occulted spectra for Her X-1, Cen X-3, and LMC X-4. We also use
the new model to constrain the emission geometry, and compare the resulting
parameters with those obtained using previously published models. Our model
sheds new light on the structure of the column, the relationship between the
ionized gas and the photons, the competition between diffusive and advective
transport, and the magnitude of the energy-averaged cyclotron scattering cross
section.
