Contribution of parsec-scale material onto the polarized X-ray spectrum
  of type-1 Seyfert galaxies
  Type-1 radio-quiet active galactic nuclei (AGN) are seen from the polar
direction and offer a direct view of their central X-ray engine. If most of
X-ray photons have traveled from the primary source to the observer with
minimum light-matter interaction, a fraction of radiation is emitted at
different directions and is reprocessed by the parsec-scale equatorial
circumnuclear region or the polar outflows. It is still unclear how much the
polarization expected from type-1 AGN is affected by radiation that have
scattered on the distant AGN components. In this paper, we examine the
contribution of remote material onto the polarized X-ray spectrum of type-1
Seyfert galaxies using radiative transfer Monte Carlo codes. We find that the
observed X-ray polarization strongly depends on the initial polarization
emerging from the disk-corona system. For unpolarized and parallelly polarized
photons (parallel to the disk), the contribution is negligible below 3 keV and
tends to increase the polarization degree by up to one percentage points at
higher energies, smoothing out the energy-dependent variations of the
polarization angle. For perpendicularly polarized corona photons, the addition
of the circumnuclear scattered (parallel) component adds to the polarization
above 10 keV, decreases polarization below 10 keV and shifts the expected 90
deg rotation of the polarization angle to lower energies. In conclusion, we
found that simulations of Seyfert-1s that do not account for reprocessing on
the parsec-scale equatorial and polar material are under- or over-estimating
the X-ray polarization by 0.1 - 1 percentage points.
