MeV Gamma-Ray Source Contribution to the Inner Galactic Diffuse Emission

Abstract

The origin of the inner Galactic emission, measured by COMPTEL with a flux of $\sim 10^{-2}{\mathrm{MeV}\mathrm{cm}}^{-2}{\mathrm{s}}^{-1}{\mathrm{sr}}^{-1}$ in the 1-30 MeV energy range from the inner Galactic region, has remained unsettled since its discovery. In this paper, we elaborate on a model of individual MeV gamma-ray sources unresolved by COMPTEL. This is conducted for sources crossmatched between the Swift-BAT and Fermi-LAT catalogs by interpolating the energy spectra in the hard X-ray and GeV gamma-ray ranges, as well as unmatched sources between the two catalogs. We find that the source contribution to the COMPTEL emission would be at least ~20%. Combined with the Galactic diffuse emission, which is not well constrained, the COMPTEL emission can be roughly reproduced in some cases.

arXiv comment14 pages, 9 figures, and 2 tables. Accepted for publication in ApJ

References in corpus (26)

• Fermi Large Area Telescope Fourth Source Catalog
• Giant Gamma-ray Bubbles from Fermi-LAT: AGN Activity or Bipolar Galactic Wind?
• Fermi-LAT Observations of the Diffuse Gamma-Ray Emission: Implications for Cosmic Rays and the Interstellar Medium
• Diffuse Galactic continuum gamma rays. A model compatible with EGRET data and cosmic-ray measurements
• The Fermi Galactic Center GeV Excess and Implications for Dark Matter
• GALPROP WebRun: an internet-based service for calculating galactic cosmic ray propagation and associated photon emissions
• Science with e-ASTROGAM (A space mission for MeV-GeV gamma-ray astrophysics)
• Cosmic ray feedback in hydrodynamical simulations of galaxy formation
• The first COMPTEL Source Catalogue
• Gamma-ray continuum emission from the inner Galactic region as observed with INTEGRAL/SPI
• High-Energy Gamma Rays from the Milky Way: Three-Dimensional Spatial Models for the Cosmic-Ray and Radiation Field Densities in the Interstellar Medium
• The IBIS soft gamma-ray sky after 1000 INTEGRAL orbits
• Imprints of Cosmic Rays in Multifrequency Observations of the Interstellar Emission
• Dual MeV Gamma-Ray and Dark Matter Observatory -- GRAMS Project
• Diffuse emission measurement with INTEGRAL/SPI as indirect probe of cosmic-ray electrons and positrons
• Indirect Detection of Dark Matter Using MeV-Range Gamma-Ray Telescopes
• Detection of the energetic pulsar PSR B1509-58 and its pulsar wind nebula in MSH 15-52 using the Fermi-Large Area Telescope
• Discovery of GeV Emission from the Circinus galaxy with the Fermi-LAT
• First Predicted Cosmic Ray Spectra, Primary-to-Secondary Ratios, and Ionization Rates from MHD Galaxy Formation Simulations
• The TeV Diffuse Cosmic Neutrino Spectrum and the Nature of Astrophysical Neutrino Sources
• Diffuse Galactic emission spectrum between 0.5 and 8.0 MeV
• Introducing the MeVCube concept: a CubeSat for MeV observations
• First observation of MeV gamma-ray universe with bijective imaging spectroscopy using the Electron-Tracking Compton Telescope aboard SMILE-2+
• Observational signatures of cosmic ray interactions in molecular clouds
• Cross-match between the latest Swift-BAT and Fermi-LAT catalogs
• Indirect Detection of Low-mass Dark Matter Through the ${\pi }^0$ and $\eta$ Windows

Cited by in corpus (4)

• Probing the Galactic Diffuse Continuum Emission with COSI
• COCOA: a compact Compton camera for astrophysical observation of MeV-scale gamma rays
• Enhancing Compton telescope imaging with maximum a posteriori estimation: a modified Richardson-Lucy algorithm for the Compton Spectrometer and Imager
• Diffuse continuum emission and large extended sources at MeV energies