Spectropolarimetry and variability of Seyfert 1.8 and 1.9 galaxies

Abstract

view Abstract Citations (135) References (39) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Spectropolarimetry and Variability of Seyfert 1.8 and 1.9 Galaxies Goodrich, Robert W. Abstract The phenomenon which produces the spectra classified as Seyfert 1.8 or 1.9 is investigated through CCD spectropolarimetry and through analysis of three highly variable objects. The Seyfert 1.9 galaxy IRAS 1958-183 has a highly polarized continuum and a broad Hα line which is ~30% polarized. The featureless continuum and probably the BLR are highly reddened. NGC 2622 (=Mrk 1218) is currently in a Seyfert 1 state, and the broad lines and featureless continuum are highly polarized. The spectropolarimetry indicates that there are two sources of light. The more highly polarized but fainter component is due to reflection from dust grains which are moving toward us at ~ -800 +/- 500 km s^-1^. The low-polarization component is probably due to transmission through aligned dust grains. IDS spectra provide enough time coverage to study the variability of NGC 2622, NGC 7603 (=Mrk 530), and Mrk 1018. The changes in flux of the broad lines and the continuum near Hα and Hβ are consistent with changes in the extinction in all cases. Improved IRAS photometry supports the conclusion that most Seyfert 1.8's and 1.9's are normal Seyfert 1's seen through a screen of dust located in or just outside of the BLR. Variability is then due to changes in the optical depth of this screen. Publication: The Astrophysical Journal Pub Date: May 1989 DOI: 10.1086/167384 Bibcode: 1989ApJ...340..190G Keywords: Active Galactic Nuclei; Astronomical Spectroscopy; Polarimetry; Seyfert Galaxies; Forbidden Transitions; H Alpha Line; H Beta Line; Infrared Astronomy Satellite; Interstellar Extinction; Optical Thickness; Astrophysics; GALAXIES: SEYFERT; POLARIZATION full text sources ADS | data products SIMBAD (24) NED (15)