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B_gg revisited: The environments of low-excitation radio galaxies and unified models

M. J. Hardcastle
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Abstract

Recent measurements of the galaxy clustering environments around intermediate-redshift radio sources have suggested a systematic environmental difference between radio galaxies and radio-loud quasars, in contradiction to the predictions of simple unified models for the two classes of object. I show that the apparent difference arises mainly as a result of the properties of low-excitation radio galaxies included in the radio-galaxy sample, which tend to lie in significantly richer environments. The environmental properties of high-excitation radio galaxies and quasars are statistically consistent in the redshift range 0.15 < z <0.4, as unified models would predict.

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M. J. Hardcastle. 2003-11-24. B_gg revisited: The environments of low-excitation radio galaxies and unified models. https://doi.org/10.1051/0004-6361%3A20035605

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