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arXiv · 0809.3100

On the relationship between BL Lacertae objects and radio galaxies

Hermine Landt·Hayley E. Bignall
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Abstract

We present deep radio images at 1.4 GHz of a large and complete sample of BL Lacertae objects (BL Lacs) selected from the Deep X-ray Radio Blazar Survey (DXRBS). We have observed 24 northern sources with the Very Large Array (VLA) in both its A and C configurations and 15 southern sources with the Australia Telescope Compact Array (ATCA) in its largest configuration. We find that in the DXRBS, as in the 1-Jy survey, which has a radio flux limit roughly ten times higher than the DXRBS, a considerable number (about a third) of BL Lacs can be identified with the relativistically beamed counterparts of Fanaroff-Riley type II (FR II) radio galaxies. We attribute the existence of FR II-BL Lacs, which is not accounted for by current unified schemes, to an inconsistency in our classification scheme for radio-loud active galactic nuclei (AGN). Taking the extended radio power as a suitable measure of intrinsic jet power, we find similar average values for low- (LBL) and high-energy peaked BL Lacs (HBL), contrary to the predictions of the blazar sequence.

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Hermine Landt, Hayley E. Bignall. 2008-09-18. On the relationship between BL Lacertae objects and radio galaxies. https://doi.org/10.1111/j.1365-2966.2008.13967.x

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