The Extragalactic Γ Ray Background
نویسنده
چکیده
One way to understand the nonthermal history of the universe is by establishing the origins of the unresolved and truly diffuse extragalactic γ rays. Dim blazars and radio/γ galaxies certainly make an important contribution to the galactic γ-ray background given the EGRET discoveries, and previous treatments are reviewed and compared with a new analysis. Studies of the γ-ray intensity from cosmic rays in star-forming galaxies and from structure formation shocks, as well as from dim GRBs, are briefly reviewed. A new hard γ-ray source class seems required from the predicted aggregate intensity compared with the measured intensity.
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تاریخ انتشار 2008