Broadband Modeling of Low-luminosity Active Galactic Nuclei Detected in Gamma Rays

Low-luminosity active galactic nuclei are more abundant and closer to us than the luminous ones but harder to explore as they are faint. We have selected the four sources, NGC 315, NGC 4261, NGC 1275, and NGC 4486, which have been detected in γ -rays by Fermi-LAT. We have compiled their long-term ra...

Full description

Saved in:
Bibliographic Details
Published in:The Astrophysical journal 2021-10, Vol.919 (2), p.137
Main Authors: Tomar, Gunjan, Gupta, Nayantara, Prince, Raj
Format: Article
Language:English
Subjects:
Active galactic nuclei
Astronomical models
Astrophysics
Broadband
Data analysis
Data points
Elastic scattering
Electrons
Emission
Galaxies
Gamma rays
Jets
Low-luminosity active galactic nuclei
Luminosity
Radiation
Radio
Radio sources (astronomy)
Spectral energy distribution
Synchrotrons
Telescopes
X ray telescopes
X-ray astronomy
XMM (spacecraft)
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Low-luminosity active galactic nuclei are more abundant and closer to us than the luminous ones but harder to explore as they are faint. We have selected the four sources, NGC 315, NGC 4261, NGC 1275, and NGC 4486, which have been detected in γ -rays by Fermi-LAT. We have compiled their long-term radio, optical, X-ray data from different telescopes, and analyzed XMM-Newton data for NGC 4486 and XMM-Newton and Swift data for NGC 315. We have analyzed the Fermi-LAT data collected over the period of 2008 to 2020 for all of them. Electrons are assumed to be accelerated to relativistic energies in subparsec-scale jets, which radiate by synchrotron and synchrotron self-Compton emission covering radio to γ -ray energies. This model can fit most of the multiwavelength data points of the four sources. However, the γ -ray data points from NGC 315 and NGC 4261 can be well fitted only up to 1.6 GeV and 0.6 GeV, respectively, in this model. This motivates us to find out the origin of the higher-energy γ -rays detected from these sources. Kiloparsec-scale jets have been observed previously from these sources in radio and X-ray frequencies. If we assume γ -rays are also produced in kiloparsec-scale jets of these sources from inverse-Compton scattering of starlight photons by ultrarelativistic electrons, then it is possible to fit the γ -ray data at higher energies. Our result also suggests that strong host galaxy emission is required to produce GeV radiation from kiloparsec-scale jets.
ISSN:0004-637X
1538-4357
DOI:10.3847/1538-4357/ac1588