The Discovery of Secondary Lobes in the Seyfert Galaxy NGC 2639

TL;DR

This paper reports the discovery of a second pair of radio lobes in NGC 2639, revealing complex magnetic field structures and jet reorientation likely caused by a minor merger, expanding understanding of AGN jet dynamics.

Contribution

It is the first report of secondary lobes in NGC 2639, showing magnetic field organization and jet reorientation due to a minor merger in a Seyfert galaxy.

Findings

Discovery of secondary radio lobes aligned nearly perpendicular to known lobes.

Magnetic field gradients indicate organized magnetic structures on kpc scales.

Jet reorientation likely caused by a minor merger event.

Abstract

We report the discovery of a secondary pair of radio lobes in the Seyfert galaxy NGC 2639 with polarization-sensitive observations with the Karl G. Jansky Very Large Array (VLA). The presence of these lobes, which are aligned nearly perpendicular to the known set of radio lobes observed in the east-west direction, has not been reported previously in the literature. The in-band rotation measure image shows gradients in both the lobes indicative of organised magnetic field structures on kpc-scales. The magnetic field structure is aligned with the jet/lobe direction in both the lobes. Based on the settled optical morphology of the host galaxy, it is likely that a minor merger that did not disrupt the host galaxy structure is responsible for the observed features in NGC 2639. This also explains the near 90$^o$ change in the jet direction; the current jet direction being the result of a new accretion disk formed by the minor merger, whose direction was a result of the angular momentum of the inflowing merger gas.