Diffuse galactic radiation
Abstract
High-energy interstellar emission is produced by interactions of cosmic-ray electrons and nuclei with the interstellar medium and low-energy radiation fields in the Milky Way. This is not only a background for point-like and extended sources studies, but also a unique tool to learn about cosmic rays and the interstellar medium. Thanks to its energy range from 20 MeV to more than 300 GeV, its large effective area and field of view, its improved angular resolution, as well as an all-sky survey strategy, the Fermi Large Area Telescope (LAT) is the best instrument to study high-energy Galactic interstellar emission, which accounts for most of the photons it detects. To disentangle degeneracies in the GeV range, complementary observations are crucial at lower and higher energy, for example by INTEGRAL/SPI, CGRO/COMPTEL or HESS, as well as all-sky radio or sub-millimeter surveys. We provide an overview of the Galactic interstellar gamma-ray emission modeling and focus on γ-ray H I emissivity and large scale structures studies performed with the LAT.
- Publication:
-
High Energy Gamma-Ray Astronomy: 5th International Meeting on High Energy Gamma-Ray Astronomy
- Pub Date:
- December 2012
- DOI:
- 10.1063/1.4772218
- Bibcode:
- 2012AIPC.1505...37C