4C 34.47: an X-shaped radio source with a relic signature of AGN axis reorientation

TL;DR

This paper reports the discovery of an X-shaped radio source with relic lobes indicating a recent reorientation of the AGN axis, providing insights into AGN evolution and jet dynamics.

Contribution

It presents the first evidence of a giant X-shaped radio source with relic lobes, supporting the rapid AGN axis reorientation scenario and suggesting multiple axis flips.

Findings

Discovery of a giant X-shaped radio source with relic lobes

Evidence supporting rapid AGN axis reorientation

Indications of multiple axis flips in the source's history

Abstract

We report a serendipitous discovery of a pair of relic lobes separated by 1.86 Mpc and straddling the radio-loud quasar 4C 34.47. The axis connecting them makes an appreciable angle with the axis of its well-known double-lobed radio structure. This object is thus a giant X-shaped source. We provide arguments supporting a rapid reorientation of the active galactic nucleus (AGN) axis as the only plausible scenario explaining the overall morphology of the object. Furthermore, we suggest that another flip of the AGN axis might have occurred in 4C 34.47 and the AGN axis happened to make a small angle with the line of sight after that. We assume that the second repositioning must have been relatively recent, hence the radio structure building up at the final position of the AGN axis is of milliarcsecond scale so far, while the main double, although no longer fuelled, has no signatures of decay yet.