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The profiles of polarized broad Hα lines in radio galaxies
(1998)
We present spectropolarimetric observations of seven broad-line radio galaxies. We find significantly polarized broad Hα emission in four objects including two, Arp 102B and 3C 390.3, which have double-peaked line profiles. ...
The obscured BLR in the radio galaxy 3C 234
(1998)
We present spectropolarimetric observations of the radio galaxy 3C 234 at optical and, for the first time, near-IR wavelengths. In agreement with previous observations we detect broad Hα in total and polarized flux, ...
Polarimetry for the Gemini telescopes
(Int Soc for Optical Engineering, 1998)
Polarimeters at optical and near-IR wavelengths are increasingly available as part of facility instruments at major observatories, and are used for a large number of astronomical programs, ranging form nearby star-forming ...
Near-infrared imaging polarimetry of Cygnus A
(1998)
We present a 2.2-μm polarization image of the nuclear regions of Cygnus A. The degree of polarization in the central 1 arcsec is (4.1±0.50) per cent, at a position angle of (23.6±3.6)°, approximately perpendicular to the ...
Beaming in Radio-Quiet AGN
(Astronomical Society of the Pacific, 1997)
We have obtained new optical spectropolarimetric data for the radio-quiet Seyfert NGC 1068, taken through apertures on the nucleus and at two positions within the ionization/scattering cone. The equivalent width of scattered ...
Polarization Properties of Active Galactic Nuclei
(Astronomical Society of the Pacific, 1997)
One of the main uses of polarimetry over the last decade has been to identify the nature of AGN that are normally hidden from direct view by an optically and geometrically thick torus, and thereby to unify different classes ...
Infrared Polarimetry and the Torus
(1997)
Polarimetry at near-infrared wavelengths is shown to be an important tool in understanding the properties of the obscuring torus in NGC1068. We present evidence for the existence of aligned grains in the torus, which produce ...
Identification of the exciting source of Herbig-Haro objects 135 and 136
(1997)
We have identified the exciting source of the Herbig-Haro objects HH135 and 136 by near-infrared polarimetric imaging of the associated extensive reflection nebula. The source is situated at the middle of the two Herbig-Haro ...
Polarization due to dichroic absorption and emission by aligned grains in dusty discs
(1997)
We present a method for calculating the infrared polarization due to absorption and emission by aligned grains distributed in a disc or a torus. The temperature distribution in the torus is calculated with the axially ...