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arXiv · 1411.1445

The Gamma Ray Opacity of the Universe -- Indirect Measurements of the Extragalactic Background Light

F. Krennrich
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Abstract

Indirect constraints on the intensity of the Extragalactic Background Light (EBL) were provided by recent studies of extragalactic sources emitting sub-TeV to multi-TeV photons. These constraints are provided thanks to the absorption of gamma rays by soft photons from the EBL (UV/optical/IR) via pair production by gamma - gamma interactions. This paper provides an overview of recent results that have led to substantially reduced uncertainties on the EBL intensity over a wide range of wavelengths from 0.1 to 15 micron.

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F. Krennrich. 2014-11-05. The Gamma Ray Opacity of the Universe -- Indirect Measurements of the Extragalactic Background Light. https://arxiv.org/abs/1411.1445

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