Abstract:
We have observed a sample of Seyfert (Sy) galaxies with global Very
Long Baseline Interferometry (VLBI) to test predictions of the unification scheme
which hypothesizes that Sys of Type 1 and of Type 2 constitute a single population
of objects. If Sy 1 and Sy 2 galaxies differ only in the orientation of the axisymmetric
active nucleus with respect to the observer, then, the parsec-scale radio structures of
the two types should be similar. We chose a sample of 10 Sy Is and 10 Sy 2s such
that the two subsamples were intrinsically similar within the framework of the
unified scheme. This was done by matching them as far as possible in orientationindependent
parameters viz., host galaxy properties and measures of intrinsic power
of the active nucleus. We present the results obtained from these observations and
their implications for the unification scheme. We also discuss the results obtained
from the measurements at all IRAS and 2-10 keY X-ray wavebands for our Sy
galaxy sample using data from the literature.
