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Anisotropic [OIII] emission in radio loud AGN

Sperello di Serego Alighieri·Andrea Cimatti·R. A. E. Fosbury·Ronald Hes
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Abstract

We present the results of spectropolarimetry of a sample of 7 powerful radio galaxies and 2 quasars with $0.07<z<0.35$ obtained to detect possible anisotropies in the [OIII] line emission, which could explain the higher [OIII] luminosity of quasars than that of radio galaxies within the framework of the Unified Model of radio-loud AGN. We detect polarized [OIII] in 4 radio galaxies, consistent with the possibility that a considerable fraction ($\sim 20%$) of the observed [OIII] emission is scattered in a similar way to the hidden nuclear continuum. However, small but detectable rotation between the polarization direction of the line and of the continuum in two radio galaxies shows that the geometry of the emitting regions can be different.

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Sperello di Serego Alighieri, Andrea Cimatti, R. A. E. Fosbury, Ronald Hes. 1997-08-22. Anisotropic [OIII] emission in radio loud AGN. https://arxiv.org/abs/astro-ph/9708205

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