Probing Radio Emission in Seyfert Galaxies on Parsec- and Kiloparsec-scales

TL;DR

This paper investigates the radio emission structures of Seyfert galaxies on parsec and kiloparsec scales, revealing insights into jet orientations and their relation to radio lobes using advanced radio observations.

Contribution

It provides new low-frequency GMRT observations of Seyfert galaxies, clarifies the connection between parsec-scale jets and kiloparsec-scale lobes, and discusses jet misalignments.

Findings

Most Seyferts are radio-loud when considering nuclear optical emission.

Kpc-scale radio lobes are common in Seyferts at low radio frequencies.

Jet-lobe misalignment suggests curved jets or no direct connection.

Abstract

Seyfert galaxies have traditionally been classified as radio-quiet active galactic nuclei. A proper consideration of the nuclear optical emission however proves that a majority of Seyferts are radio-loud. Kpc-scale radio lobes/bubbles are in fact revealed in sensitive observations at low radio frequencies of several Seyferts. Through the use of very long baseline interferometry, we have been able to determine the direction of the parsec-scale jets in some of these Seyfert galaxies. The misalignment between the parsec-scale jets and the kpc-scale lobes that is typically observed, is either suggestive of no connection between the two, or the presence of curved jets that power the radio lobes. In this context, we briefly discuss our new low radio frequency GMRT observations of two Seyfert galaxies with lobes.