Revised optical classification of a sample of gamma-ray-emitting active galactic nuclei with GTC and VLT
Year: 2025
Type: article
Abstract: We report the results of the optical follow-up of a sample of γ -ray-emitting active galactic nuclei (AGNs). New high-quality optical spectra were obtained using the Gran Telescopio Canarias with the Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy and the European Southern Observatory’s Very Large Telescope Unit Telescope 1 with the FOcal Reducer and low dispersion Spectrograph 2. From the analysis of these spectra, we confirmed the previous narrow-line Seyfert 1 (NLS1) classification for four objects and discovered two new NLS1s, bringing the total number of optically confirmed γ -NLS1s to 26. We also identified two ambiguous cases between NLS1 and intermediate Seyfert (IS), three ISs, one broad-line Seyfert 1, and one Seyfert 2. Based on the new spectra, we calculated black hole masses ranging from 10 6.25 to 10 9.32 M ⊙ and Eddington ratios spanning 0.05 to 2.07. This reclassification provides support for the scenario in which AGNs with relatively low black hole masses are capable of launching powerful relativistic jets and contributes to our broader understanding of γ -ray-emitting AGNs.
Source: Astronomy and Astrophysics
Authors: B. Dalla Barba, L. Foschini, M. Berton, E. Järvelä, P. Marziani, S. Ciroi, E. Dalla Bontá, L. Crepaldi, A. Vietri, S. Antón, M. J. M. Marchã, P. Condó, C. Mazzucchelli
Institutions: University of Insubria, Brera Astronomical Observatory, National Institute for Astrophysics, European Southern Observatory, European Southern Observatory, Texas Tech University, Osservatorio Astronomico di Padova, University of Padua, University of Lancashire, Osservatorio Astronomico di Cagliari, Centro de Física da Universidade de Coimbra, University of Coimbra, University College London, University of Rome Tor Vergata, Universidad Diego Portales
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
OpenAlex ID: W7106821592