Modeling the gamma-ray emission in the Galactic Center with a fading cosmic-ray accelerator
arXiv:1609.01069 · doi:10.3847/1538-4357/833/2/200
Abstract
Recent HESS observations of the ~200 pc scale diffuse gamma-ray emission from the central molecular zone (CMZ) suggest the presence of a PeV cosmic-ray accelerator (PeVatron) located in the inner 10 pc region of the Galactic Center. Interestingly, the gamma-ray spectrum of the point-like source (HESS J1745-290) in the Galactic Center shows a cutoff at ~10 TeV, implying a cutoff around 100 TeV in the cosmic-ray proton spectrum. Here we propose that the gamma-ray emission from the inner and the outer regions may be explained self-consistently by run-away protons from a single, yet fading accelerator. In this model, gamma rays from the CMZ region are produced by protons injected in the past, while gamma rays from the inner region are produced by protons injected more recently. We suggest that the blast wave formed in a tidal disruption event (TDE) caused by the supermassive black hole (Sgr A*) could serve as such a fading accelerator. With typical parameters of the TDE blast wave, gamma-ray spectra of both the CMZ region and HESS J1745-290 can be reproduced simultaneously. Meanwhile, we find that the cosmic-ray energy density profile in the CMZ region may also be reproduced in the fading accelerator model when appropriate combinations of the particle injection history and the diffusion coefficient of cosmic rays are adopted.
arXiv comment16 pages, 4 figures, to appear in ApJ
References in corpus (31)
- The Galactic Center Massive Black Hole and Nuclear Star Cluster
- Energy spectra of gamma-rays, electrons and neutrinos produced at proton-proton interactions in the very high energy regime
- Detection of the Characteristic Pion-Decay Signature in Supernova Remnants
- A relativistic jetted outburst from a massive black hole fed by a tidally disrupted star
- Acceleration of petaelectronvolt protons in the Galactic Centre
- Swift J2058.4+0516: Discovery of a Possible Second Relativistic Tidal Disruption Flare?
- Rates of Stellar Tidal Disruption as Probes of the Supermassive Black Hole Mass Function
- Revised Rates of Stellar Disruption in Galactic Nuclei
- Cosmic ray acceleration and escape from supernova remnants
- Discovery of very high energy gamma-ray emission coincident with molecular clouds in the W28 (G6.4-0.1) field
- Global cosmic-ray related luminosity and energy budget of the Milky Way
- Fermi LAT Observations of the Supernova Remnant W28 (G6.4-0.1)
- Attenuation of VHE gamma rays by the Milky Way interstellar radiation field
- Swift J1112.2-8238: A Candidate Relativistic Tidal Disruption Flare
- Analytic Solution for Self-regulated Collective Escape of Cosmic Rays from their Acceleration Sites
- High energy gamma rays from the massive black hole in the Galactic Center
- Spectrum and variability of the Galactic Center VHE gamma-ray source HESS J1745-290
- Galactic center at very high-energies
- Fermi-LAT Discovery of GeV Gamma-ray Emission from the Vicinity of SNR W44
- Towards a Model for the Progenitors of Gamma-Ray Bursts
- First detection of GeV emission from an ultraluminous infrared galaxy: Arp 220 as seen with the Fermi Large Area Telescope
- Inverse Compton Scenarios for the TeV Gamma-Ray Emission of the Galactic Centre
- Relativistic diffusion processes and random walk models
- Stochastic Acceleration in the Galactic Center HESS Source
- Properties of Nearby Starburst Galaxies Based on their Diffuse Gamma-ray Emission
- Superluminal problem in diffusion of relativistic particles and its phenomenological solution
- Diffuse Gamma-ray Emission from the Galactic Center - A Multiple Energy Injection Model
- On transition of propagation of relativistic particles from the ballistic to the diffusion regime
- VHE gamma ray absorption by galactic interstellar radiation field
- Cosmic Ray Origins in Supernova Blast Waves
- The Gamma-ray Afterglows of Tidal Disruption Events
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- Cosmic ray production in supernovae
- Sagittarius A* as an Origin of the Galactic PeV Cosmic Rays?
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- Inefficient cosmic ray diffusion around Vela X : constraints from H.E.S.S. observations of very high-energy electrons
- HESS J1745290 spectrum explained by a transition in the diffusion regime of PeV cosmic rays in the Sgr A* accretion flow
- Stochastic dynamics from maximum entropy in action space
- TeV-PeV Gamma-ray and Neutrino Emission in the Galactic Plane