A Multi-Wavelength Study of the Nature of Type 1.8/1.9 Seyfert Galaxies
  We focus on determining the underlying physical cause of a Seyfert galaxy's
appearance as type a 1.8 or 1.9. Are these "intermediate" Seyfert types typical
Seyfert 1 nuclei with reddened broad-line regions? Or are they objects with
intrinsically weak continua and broad emission lines? We compare measurements
of the optical reddening of the narrow and broad-line regions with each other
and with the X-ray column derived from XMM-Newton 0.5-10 keV spectra to
determine the presence and location of dust in the line of sight. We also
searched the literature to see if the objects showed evidence for broad-line
variability, and determined if the changes were consistent with a change in
reddening or a change in the intrinsic ionizing continuum flux. We find that 10
of 19 objects previously classified as Seyfert 1.8/1.9s received this
designation due to their low continuum flux. In four objects the classification
was due to BLR reddening, either by the torus or dust structures in the
vicinity of the NLR; in the remaining five objects there is not sufficient
evidence to favor one scenario over the other. These findings imply that, in
general, samples of 1.8/1.9s are not suitable for use in studies of the gas and
dust in the central torus.
