High Energy Astrophysics pp 321-327 | Cite as
The Diffuse X-Ray Background and Other Cosmic Backgrounds
Abstract
Cosmologists are familiar with the cosmicmicrowave background. This is, however, not the only source of radiation that cannot be immediately identifiedwith individual sources. A population of weak sources observed with an instrument of limited angular resolution and low sensitivity will look like a diffuse source covering an extended region of the sky. The instrument observing this population will indeed register a very small number of photons from each source, and will not allow the observer to distinguish the individual sources. Since at some limit, all our instruments have a low sensitivity and a limited angular resolution, we meet this case in several wavebands, and in particular in the X-rays where early instruments had no focusing systems beyond collimators.
Keywords
Diffuse Emission Cosmic Microwave Background Temperature Neutrino Background Stellar Collapse Rocket FlightReferences
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