A New Sample of Gamma-Ray Emitting Jetted Active Galactic Nuclei—Preliminary Results

Abstract

We are compiling a new list of gamma-ray jetted active galactic nuclei (AGN), starting from the fourth catalog of point sources of the Fermi Large Area Telescope (LAT). Our aim is to prepare a list of jetted AGN with known redshifts and classifications to be used to calibrate jet power. We searched in the available literature for all the published optical spectra and multiwavelength studies useful to characterize the sources. We found new, missed, or even forgotten information leading to a substantial change in the redshift values and classification of many sources. We present here the preliminary results of this analysis and some statistics based on the gamma-ray sources with right ascension within the interval 0h--12h (J2000). Although flat-spectrum radio quasars and BL Lac objects are still the dominant populations, there is a significant increase in the number of other objects, such as misaligned AGN, narrow-line Seyfert 1 galaxies, and Seyfert galaxies. We also introduced two new classes of objects: changing-look AGN and ambiguous sources. About one third of the sources remain unclassified.

Jet power, intrinsic γ-ray luminosity, and accretion in jetted AGNs

“…We carefully checked the sample of Paliya et al ( 2021) and compared it with the source classification of Abdollahi et al ( 2020 ) and Foschini et al ( 2021 ), and found that 17 γ -ray narrow-line Seyfert 1 galaxies ( γ NLS1s) were included in the sample of Paliya et al ( 2021 ). We only consider these sources with 1.4 GHz radio flux from the NED.…”

Spectacular 240 kpc double-sided relativistic jets in a spiral-hosted narrow-line Seyfert 1 galaxy

“…Despite multiple observations suggesting that NLS1s have low-mass BHs, several NLS1s have been detected at γ-rays (Abdo et al 2009a,b;Paliya et al 2018;Foschini et al 2021), confirming the presence of powerful relativistic jets in them. This goes against the fact that, until recently, it was believed that powerful jets could only be harboured in elliptical galaxies, hosting the most massive supermassive BHs (Urry & Padovani 1995;Franceschini et al 1998;Kotilainen et al 2005).…”

Some Notes About the Current Researches on the Physics of Relativistic Jets

“…We also found many reports on sources displaying strong changes in the optical spectra, from line-dominated spectra to featureless ones (changing-look AGN). We also found that many of the commonly adopted redshifts were not correct, because of mere transcription errors from the paper to the database, old and outdated information, lower limits taken as measurements, and many other problems (Foschini et al, 2021). This is really a time-consuming work, but nonetheless it must be done, otherwise, we will continue to study and to draw fake conclusions on strongly biased samples.…”