γ-rays as a diagnostic of the origin of core radiation in low-luminosity active galactic nuclei
Abstract
The respective contribution of disc and jet components to the total emission in low-luminosity active galactic nuclei (LLAGNs) is an open question. This paper suggests that γ-rays emitted from electrons accelerated in jets could be a direct diagnostic tool for a jet component to the total emission. We demonstrate γ-ray flux from jets based on a synchrotron self-Compton model on the assumption that radio and X-rays are dominantly produced from jets in the case of a high state of a nearby LLAGN, NGC 4278. We also survey parameter space in the model. Observational properties of LLAGNs in radio and X-ray bands allow to constrain physical parameters in an emission region. The size of the emission region R is limited to 1016≤R≤ 1017.5 cm if the observed tight correlation between radio and X-ray emission originates from the same jet component. If the beaming factor of the emission region is close to the observed parsec scale jet of NGC 4278 and R∼ 1016 cm, the γ-rays may be detected by the Cherenkov Telescope Array and the jet domination can be tested in the near future.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- May 2011
- DOI:
- 10.1111/j.1365-2966.2011.18264.x
- arXiv:
- arXiv:1012.5403
- Bibcode:
- 2011MNRAS.413.1845T
- Keywords:
-
- galaxies: active;
- galaxies: individual: NGC 4278;
- galaxies: jets;
- galaxies: nuclei;
- gamma-rays: galaxies;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 8 pages, 3 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society