Implications of cosmological gamma-ray absorption
نویسندگان
چکیده
منابع مشابه
Implications of Cosmological Gamma-Ray Absorption II. Modification of gamma-ray spectra
Bearing on the model for the time-dependent metagalactic radiation field developed in the first paper of this series, we compute the gamma-ray attenuation due to pair production in photon-photon scattering. Emphasis is on the effects of varying the star formation rate and the fraction of UV radiation assumed to escape from the star forming regions, the latter being important mainly for high-red...
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Gamma-ray absorption due to γγ-pair creation on cosmological scales depends on the line-of-sight integral of the evolving density of low-energy photons in the Universe, i.e. on the history of the diffuse, isotropic radiation field. Here we present and discuss a semi-empirical model for this metagalactic radiation field based on stellar light produced and reprocessed in evolving galaxies. With a...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2002
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20020211