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Infrared emission from radio-loud active nuclei

Ilse M. van Bemmel·Peter D. Barthel·Thijs de Graauw
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Abstract

In order to test the unification scheme for double-lobed radio sources, the far-infrared properties of matched samples of radio-galaxies and radio-loud quasars were studied using ISOPHOT. The quasar data were complemented with nearly simultaneous submillimeter and centimeter radio data. The results show that quasars are generally brighter than radio-galaxies in their far-infrared output and that beamed non-thermal radiation must be excluded as source for this infrared excess. However, non-thermal flares or optically thick tori can still reconcile these results with the unification scheme.

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Ilse M. van Bemmel, Peter D. Barthel, Thijs de Graauw. 1999-02-09. Infrared emission from radio-loud active nuclei. https://arxiv.org/abs/astro-ph/9902143

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