Gradient model analysis of EGRET diffuse Galactic γ-ray emission.
Abstract
We have analysed the EGRET Phase 1+2 sky survey data using a model for the diffuse Galactic emission which the γ-ray emissivity per atom is a function of Galactocentric radius. The CO-to-H_2_ conversion factor is determined as 1.9+/-0.2x10^20^mols.cm^-2^/(K.km/s) for E=100-10000MeV; no significant energy dependence of this quantity is detected. The emissivity gradient is rather small, consistent with earlier COS-B results. The inverse-Compton component is detected at all energies. Emissivity and intensity spectra of the emission are presented. Above 1GeV we confirm the excess above that expected for π^0^-decay alredeay noted by the EGRET team.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- April 1996
- Bibcode:
- 1996A&A...308L..21S
- Keywords:
-
- GAMMA RAYS: GENERAL;
- COSMICS RAYS: INTERSTELLAR MEDIUM: CLOUDS: GENERAL;
- INTERSTELLAR MEDIUM: GENERAL