  An analytical model for the Maxwell radiation field in an axisymmetric
galaxy, proposed previously, is first checked for its predictions of the
spatial variation of the spectral energy distributions (SEDs) in our Galaxy.
First, the model is summarized. It is now shown how to compute the SED with
this model. Then the model is adjusted by asking that the SED predicted at our
local position in the Galaxy coincide with the available observations. Finally
the first predictions of the model for the spatial variation of the SED in the
Galaxy are compared with those of a radiation transfer model. We find that the
two predictions do not differ too much. This indicates that, in a future work,
it should be possible with the present model to check if the "interaction
energy" predicted by an alternative, scalar theory of gravitation, contributes
to the dark matter.
  Keywords: Disk galaxy; interstellar radiation field; axial symmetry;
electromagnetic field; Milky Way.
