Radiation fields in star-forming galaxies: the disk, thin disk and bulge
  We provide and describe a library of diffuse stellar radiation fields in
spiral galaxies derived using calculations of the transfer of stellar radiation
from the main morphological components - disks, thin disks, and bulges -
through the dusty interstellar medium. These radiation fields are
self-consistent with the solutions for the integrated panchromatic spectral
energy distributions (SEDs) previously presented using the same model. Because
of this, observables calculated from the radiation fields, such as gamma-ray or
radio emission, can be self-consistently combined with the solutions for the
ultraviolet/optical/submillimeter SEDs, thus expanding the range of
applicability of the radiation transfer model to a broader range of wavelengths
and physical quantities. We also give analytic solutions for radiation fields
in optically thin stellar disks, in stellar disks with one dust disk and in
stellar disks with two dust disks. The analytic solutions for the direct light
are exact and can be used as benchmarks. The analytic solutions with scattering
are only approximate, becoming exact only in the extreme optically thick limit.
We find strongly contrasting solutions for the spatial distribution of the
radiation fields for disks, thin disks and bulges. For bulges we find a strong
dependence of the radiation fields on Sersic index.
