Investigating possible unification of Seyfert galaxies and blazars in Fermi-LAT sample

TL;DR

This study analyzes radio, X-ray, and gamma-ray data of Seyfert galaxies and blazars from Fermi-LAT and INTEGRAL, revealing potential unification and evolutionary links among these active galactic nuclei.

Contribution

It provides evidence supporting the unification scheme of Seyfert galaxies and blazars through multi-wavelength emission analysis and statistical tests.

Findings

Seyfert galaxies, BL Lacs, and FSRQs follow a sequence suggesting unification.

Similar X-ray luminosities indicate a fundamental connection.

Differences in radio luminosity imply an evolving structure.

Abstract

Statistical analyses are invaluable methods used to understand intrinsic emission processes and the unification of extragalactic radio sources. In this paper, we collected radio, X-ray and {\gamma}-ray data of blazars from the Fermi-LAT and Seyfert galaxies from the INTEGRAL survey and investigated the relationship between the emission properties of Seyfert galaxies and blazar subclasses of flat-spectrum radio quasars (FSRQs) and BL Lac subclasses (BL Lacs). The results show from the average values that these objects follow a sequence that is indicative of probable Seyfert galaxies - BL Lacs - FSRQs unification. We discovered that Seyfert galaxies, BL Lacs and FSRQs share similar emission characteristics in X-ray luminosity (LX-ray), suggestive of the fundamental connection while the {\gamma}-ray and radio luminosities (L{\gamma}-ray and Lradio) of Seyfert galaxies are the least powerful, signifying an evolving structure. From the two-dimensional Kolmogorov-Smirnov test (K-S test), we found that Seyfert galaxies differ from the blazar subclasses in Lradio while there is no significant difference between them in LX-ray and L{\gamma}-ray which implies that high energy emissions in Seyfert galaxies and blazar subclasses may come from the same emission mechanism. Significant positive correlations exist between the high energy luminosities (X-ray and {\gamma}-ray bands) and the low energy component (radio) within the whole sample of blazars and Seyfert galaxies implying a form of connection between them. These results are not only consistent with the prediction of the unified scheme for blazars but also show that Seyfert galaxies have an evolutionary link with blazar subclasses.