Abstract
BL Lac type objects1,2 have many properties in common with highly polarized quasars, and indeed appear to be distinguishable from these more active of the quasars only by the absence of prominent optical emission lines and perhaps the extremeness of their variability3,4. It has been suggested that BL Lacs and active quasars should be regarded as one family of active objects, termed Blazars3, in which special geometrical effects and probably relativistic beaming5,6 have an important role. Crucial to such suggestions is the radio structure of the sources4,5, and we report here observations which show that the BL Lacs do indeed possess the general core–halo morphology predicted by the Blazar models, although there is an important difference to the quasars in that compact jet-like features are much less conspicuous.
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Stannard, D., McIlwrath, B. Extended radio structure of BL Lac type objects. Nature 298, 140–142 (1982). https://doi.org/10.1038/298140a0
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DOI: https://doi.org/10.1038/298140a0
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