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New Insights into the Quasar Type1/Type2 Dichotomy from Correlations between Quasar Host Orientation and Polarization

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 نشر من قبل Benoit Borguet
 تاريخ النشر 2008
  مجال البحث فيزياء
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We investigate correlations between the direction of the optical linear polarization and the orientation of the host galaxy/extended emission for type1 and type2 radio-loud and radio-quiet quasars. We have used high resolution Hubble Space Telescope data and a deconvolution process to obtain a good determination of the host galaxy/extended emission (EE) position angle. With these new measurements and a compilation of data from the literature, we find a significant correlation, different for type1 and type2 objects, between the linear polarization position angle and the orientation of the EE, suggesting scattering by an extended UV/blue region in both types of objects. Our observations support the extension of the Unification Model to the higher luminosity AGNs like the quasars, assuming a two component scattering model.

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