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Misdirected Quasars in Distant Radio Galaxies

Published online by Cambridge University Press:  19 July 2016

Sperello di Serego Alighieri
Affiliation:
Osservatorio Astrofisico di Arcetri Largo E. Fermi 5, I-50125, Firenze, Italy
Andrea Cimatti
Affiliation:
European Southern Observatory Karl–Schwarzschild Str.2, D-8046, Garching bei München, Germany

Abstract

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We present the results of recent spectro–polarimetry and imaging–polarimetry of distant radio galaxies which show: (1) broad polarized permitted emission lines, (2) narrow unpolarized forbidden emission lines, (3) a flat (in fλ) polarized UV continuum and (4) an absorption feature, probably interstellar. The direction of the E vector of polarization is always perpendicular to the optical/radio axis. These observations are strong evidence that these objects harbour a quasar, which is visible only through scattering by the interstellar medium of the galaxy. The continuum polarization drops to the red of the 4000Å break, suggesting dilution by an evolved stellar population. A two-component model made of a dust scattered quasar and an evolved stellar population reproduces well the polarization and the spectral energy distribution, including the IR data.

Type
Multi-wavelength Continuum Emission of AGN
Copyright
Copyright © Kluwer 1994 

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