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arXiv · 2103.12884

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

P. Lira·M. Kishimoto·R. W. Goosmann·R. Campos·D. Axon·M. Elvis·A. Lawrence·B. M. Peterson·A. Robinson
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Abstract

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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P. Lira, M. Kishimoto, R. W. Goosmann, R. Campos, D. Axon, M. Elvis, A. Lawrence, B. M. Peterson, A. Robinson. 2021-03-23. Spectropolarimetry of NGC3783 and Mrk509: Evidence for powerful nuclear winds in Seyfert 1 Galaxies. https://doi.org/10.1093/mnras/stab1751

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