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Spectropolarimetry of NGC3783 and Mrk509: Evidence for powerful nuclear winds in Seyfert 1 Galaxies

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 نشر من قبل Paulina Lira
 تاريخ النشر 2021
  مجال البحث فيزياء
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We present results from high signal-to-noise optical spectropolarimetric observations of the Seyfert 1 galaxies NGC783 and Mrk509 in the 3500-7000 A range. We find complex structure in the polarized emission for both objects. In particular, Position Angle (PA) changes across the Balmer lines show a distinctive M-shaped profile that had not been observed in this detail before, but could represent a common trait in Seyfert 1 galaxies. In fact, while this shape is observed in all Balmer lines in NGC3783, Mrk509 transitions into a M-shaped PA profile for higher transitions lines. We have modeled the observed profiles using the STOKES radiative transfer code and assuming that the scattering region is co-spatial with the BLR and outflowing. The results give compelling new evidence for the presence of nuclear winds in these two Seyfert 1 galaxies.



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