a New Look at the Diffuse Gamma-Ray Spectrum Between 0. 1 and 200 Mev
Abstract
Recent measurements of the diffuse spectrum of cosmic gamma-rays using Compton telescopes give evidence for a spectrum flatter than E to the -2 in the energy range 0.5-8 MeV. It is now well established that the gamma-ray spectrum is much steeper than this in the energy range 0.1-0.5 MeV, and also at energies greater than 30 MeV. Therefore, the flatter spectrum may be interpreted as a bump in the extragalactic diffuse spectrum. The existence of the bump is found to be only weakly dependent on assumptions regarding the atmospheric component. Interpretations of the spectral bump in terms of the integrated spectra of galaxies with spectra flatter than E to the -2 at low energies and with a sharp spectral break at a few MeV, or as a diffuse cosmological component, are considered.
- Publication:
-
International Cosmic Ray Conference
- Pub Date:
- 1981
- Bibcode:
- 1981ICRC....1..247W
- Keywords:
-
- Astronomical Spectroscopy;
- Cosmic Rays;
- Diffuse Radiation;
- Gamma Ray Spectra;
- Radiation Measurement;
- Compton Effect;
- Galactic Radiation;
- Gamma Ray Astronomy;
- Telescopes;
- Space Radiation;
- ASTRONOMICAL SPECTROSCOPY;
- COSMIC RAYS;
- DIFFUSE RADIATION;
- GAMMA RAY SPECTRA;
- RADIATION MEASUREMENT;
- COMPTON EFFECT;
- GALACTIC RADIATION;
- GAMMA RAY ASTRONOMY;
- TELESCOPES