Spatial and Temporal Variations of the Diffuse Iron 6.4 keV Line in the Galactic Center Region

Abstract

We analyze the diffuse Fe I K-alpha line generated in the diffuse interstellar molecular hydrogen by primary photons or subrelativistic protons injected by Sagittarius (Sgr) A*. We showed that unlike emission from compact molecular clouds, this emission can be permanently observed in the directions of the Galactic center. We conclude that the diffuse emission of 6.4 keV line observed at present is probably due to Fe I K-alpha vacancy production by primary photons if the X-ray luminosity of Sgr A* was about Lx ~ 10^39-10^40 erg/s. In principle these data can also be described in the framework of the model when the 6.4 keV line emission is generated by subrelativistic protons generated by accretion onto the central black hole but in this case extreme parameters of this model are necessary.

15 pages, 7 figues. Accepted for publication in PASJ

References in corpus (6)

• The ASTRO-H Mission
• New Evidence for High Activity of the Super-Massive Black Hole in our Galaxy
• K-shell Emission of Neutral Iron Line from Sgr B2 Excited by Subrelativistic Protons
• Global Distribution of Fe K alpha Lines in the Galactic Center Region Observed with the Suzaku Satellite
• Fe Ka line emission from the Arches cluster region - evidence for ongoing particle bombardment?
• A past capture event at Sagittarius A* inferred from the fluorescent X-ray emission of Sagittarius B clouds

Cited by in corpus (4)

• Interacting Cosmic Rays with Molecular Clouds: A Bremsstrahlung Origin of Diffuse High Energy Emission from the Inner 2deg by 1deg of the Galactic Center
• Galactic Center Research: Manifestations of the Central Black Hole
• The origin of the 6.4 keV line emission and H${}_2$ ionization in the diffuse molecular gas of the Galactic center region
• The Galactic Center: Not an Active Galactic Nucleus