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FIRST `Winged' and `X'-shaped Radio Source Candidates

C. C. Cheung·A. Springmann
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Abstract

A small number of double-lobed radio galaxies are found with an additional pair of extended low surface brightness `wings' of emission giving them a distinctive `X'-shaped appearance. One popular explanation for the unusual morphologies posits that the central supermassive black hole (SMBH)/accretion disk system underwent a recent realignment; in a merger scenario, the active lobes mark the post-merger axis of the resultant system. However, this and other interpretations are not well tested on the few (about one dozen) known examples. In part to remedy this deficiency, a large sample of winged and X-shaped radio sources is being compiled for a systematic study. An initial sample of 100 new candidates is described as well as some of the follow-up work being pursued to test the different scenarios.

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C. C. Cheung, A. Springmann. 2006-12-14. FIRST `Winged' and `X'-shaped Radio Source Candidates. https://arxiv.org/abs/astro-ph/0612398

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