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Date and Time of the Query: 2019-06-24 T15:36:10 PDT
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For refcode 1990MNRAS.247..327B:
Retrieve 18 NED objects in this reference.
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NED Abstract

Copyright by Royal Astronomical Society. 1990MNRAS.247..327B An optical and near-infrared polarization survey of early-type radio galaxies C. Brindle and J. H. Hough Division of Physical Sciences, Hatfield Polytechnic, Hatfield, Herts AL10 9AB J. A. Bailey UK Infrared Telescope Unit, 665 Komohana Street, Hilo, Hawaii 96720, USA D. J. Axon University of Manchester, Nuffield Radio Astronomy Laboratories, Jodrell Bank, Macclesfield, Cheshire SK11 9DL W. B. Sparks Space Telescope Scince Institute, 3700 San Martin Drive, Baltimore, USA Accepted 1990 June 11. Received 1990 June 4; in original form 1989 December 28 SUMMARY We present optical and near-infrared (0.43-2.2 micron) polarization and flux density measurements of 18 early-type radio galaxies which show excess 10-micron infrared emission. The observed degrees of polarization are generally small (P<1 per cent) and for many galaxies there is likely to be significant contamination from interstellar polarization produced in our Galaxy. IC 5063 and NGC 5128, and possibly NGC 1052 and 838, have degrees of polarization which show a likely increase in the near-infrared. For the first three, the increase in polarization can be explained by dilution with unpolarized galaxy light of a relatively steep-spectrum source, having high and wavelength-dependent polarization. This source may be a low-luminosity BL Lac, viewed at a large angle to the radio jet axis, but the lack of confirmed polarization variability in the optical and the near-infrared allows for alternative explanations, such as scattering. There is a tendency for the polarization E-vector (especially in the infrared) to be perpendicular to the radio axis. For some galaxies, the wavelength-dependence of polarization is consistent with that produced by the transmission of light through aligned dust grains, with the optical polarization E-vector parallel to a dust lane. There is no evidence for polarization variability from our few repeat measurements of individual galaxies. We review the evidence for radio ellipticals containing a low-luminosity BL Lac type source.
Retrieve 18 NED objects in this reference.
Please click here for ADS abstract

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