The bremsstrahlung component of the diffuse galactic gamma-ray emission at MeV energies
Abstract
Under the assumption that most of the observed gamma-ray flux below 30 MeV is produced by electron bremsstrahlung, restrictions on the energy spectrum of cosmic-ray electrons in interstellar space below 100 MeV are derived. The most accurate bremsstrahlung production cross sections of Koch and Motz and of Blumenthal and Gould are used in order to derive the bremsstrahlung production spectrum in interstellar space down to 10 keV-photon energies. If the low-energy gamma-ray emission, as seen by most observers, is indeed produced by electron bremsstrahlung, then a high interstellar electron flux at MeV energy results, which - at higher energies connects to the upper limit derived by Cummings, Stone, and Vogt. Such a high low-energy electron flux would be able to explain the ionization rate of 1 x 10 to the -15th ion pairs/(H-atoms) in H I regions.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 1984
- DOI:
- 10.1086/161952
- Bibcode:
- 1984ApJ...279..817S
- Keywords:
-
- Bremsstrahlung;
- Electron Flux Density;
- Galactic Cosmic Rays;
- Gamma Ray Astronomy;
- Interstellar Matter;
- Diffuse Radiation;
- Energy Spectra;
- Gamma Ray Spectra;
- H I Regions;
- Space Radiation