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arXiv · 2501.08141

Magnetic Field Structures In and Around Seyfert Galaxy Outflows

Salmoli Ghosh·P. Kharb·B. Sebastian·J. Gallimore·A. Pasetto·C. P. O'Dea·T. Heckman·S. A. Baum
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Abstract

We present radio polarimetric images of 12 Seyfert and Low-Ionization Nuclear Emission-line Region (LINER) galaxies belonging to the Centre for Astrophysics (CfA)+12 micron sample exhibiting kiloparsec-scale radio outflows (KSRs). These observations have been carried out at 10 GHz with Karl G. Jansky Very Large Array (VLA) in D-array and at 1.4 GHz with the BnA$\rightarrow$A array configurations. We find signatures of organized magnetic (B-) field structures in the cores, jets and lobes of these galaxies. The linear polarization fraction varies from a few per cent in the cores to $47\pm18$ per cent in the lobes. The inferred B-fields are toroidal in the cores of several sources making them consistent with the presence of either a sheath-like or a wind-like component surrounding the jet. The in-band spectral index images typically show the presence of flat/inverted spectrum cores and steep spectrum lobes. Radio cores with flatter spectra are found to have lower Eddington ratios while the steeper ones have higher. A strong correlation is observed between the Seyfert/LINER radio outflow properties and the mass of the supermassive black holes (SMBHs); correlations with Eddington ratios are weaker. We find signatures of jet-medium interaction and both positive and negative AGN feedback in these sources. Overall, our study indicates that radio-quiet (RQ) AGN with KSRs possess radio outflows driven by magnetic fields anchored to their black holes - accretion disks, which significantly impact their environments.

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Salmoli Ghosh, P. Kharb, B. Sebastian, J. Gallimore, A. Pasetto, C. P. O'Dea, T. Heckman, S. A. Baum. 2025-01-14. Magnetic Field Structures In and Around Seyfert Galaxy Outflows. https://arxiv.org/abs/2501.08141

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