Diffuse gamma-ray emission from the Galactic center and implications of its past activities
High Energy Astrophysical Phenomena
2017-02-22 v1 Astrophysics of Galaxies
Abstract
It has been indicated that low-luminosity active galactic nuclei (LLAGNs) are accelerating high-energy cosmic-ray (CR) protons in their radiatively inefficient accretion flows (RIAFs). If this is the case, Sagittarius A* (Sgr A*) should also be generating CR protons, because Sgr A* is a LLAGN. Based on this scenario, we calculate a production rate of CR protons in Sgr A* and their diffusion in the central molecular zone (CMZ) around Sgr A*. The CR protons diffusing in the CMZ create gamma-rays through pp interaction. We show that the gamma-ray luminosity and spectrum are consistent with observations if Sgr A* was active in the past.
Keywords
Cite
@article{arxiv.1610.00711,
title = {Diffuse gamma-ray emission from the Galactic center and implications of its past activities},
author = {Yutaka Fujita and Shigeo S. Kimura and Kohta Murase},
journal= {arXiv preprint arXiv:1610.00711},
year = {2017}
}
Comments
Proceedings of IAU Symposium 322 (The Multi-Messenger Astrophysics of the Galactic Centre)