Diffuse galactic hard X-ray and low-energy gamma-ray continuum
We summarize some recent results related to observations and interpretation of hard X-ray and low-energy 7-ray diffuse Galactic continuum emission. Combined spectra based on data from OSSE, COMPTEL and EGRET are presented. In the energy range 1-30 MeV covered by COMPTEL the spectrum of the diffuse emission has been measured and is consistent with a combination of bremsstrahlung and inverseCompton emission; spatial analysis shows strong evidence for a component with a wide latitude extent which is plausibly identified with inverse-Compton. Molecular hydrogen appears to be only a weak γ-ray emitter at low energies, which may indicate reduced MeV cosmic-ray electron density in molecular clouds. New data on the hard X-ray diffuse Galactic emission from OSSE indicates the need for a dramatic low-energy upturn in the electron spectrum, or for some other additional component of γ-ray emission. The interstellar electron spectrum has been computed using a diffusive halo model and the resulting bremsstrahlung and inverse-Compton emission is compared with the observations.
Publication Source (Journal or Book title)
Astronomy and Astrophysics Supplement Series
Strong, A., Bennett, K., Bloemen, H., Diehl, R., Hermsen, W., Purcell, W., Schönfelder, V., Stacy, J., Winkler, C., & Youssefi, G. (1996). Diffuse galactic hard X-ray and low-energy gamma-ray continuum. Astronomy and Astrophysics Supplement Series, 120 (4), 381-387. Retrieved from https://repository.lsu.edu/physics_astronomy_pubs/5190