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arXiv · astro-ph/9705246

Limits on the Isotropic Diffuse Flux of Ultrahigh Energy Gamma-Radiation

MIA Collaboration
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Abstract

Diffuse ultrahigh energy gamma-radiation can arise from a variety of astrophysical sources, including the interaction of extremely high energy cosmic rays with the 3K microwave background radiation or the collapse of topological defects created in the early Universe. We describe a sensitive search for diffuse gamma-rays at ultrahigh energies using the CASA-MIA experiment. An isotropic flux of radiation is not detected, and we place stringent upper limits on the fraction of the gamma-ray component relative to cosmic rays (less than one part in 10,000) at energies from 570 TeV to 55,000 TeV. This result represents the first comprehensive constraint on the gamma-ray flux at these energies.

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BibTeXRIS

MIA Collaboration. 1997-05-30. Limits on the Isotropic Diffuse Flux of Ultrahigh Energy Gamma-Radiation. https://doi.org/10.1103/physrevlett.79.1805

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