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The Origin of the Knee in the Cosmic-Ray Energy Spectrum

A. D. Erlykin·A. W. Wolfendale
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Abstract

A sudden steepening of the cosmic-ray energy spectrum (the knee) is observed at an energy of about 3 PeV (1 PeV = 10$^{15}$eV). The recent results on extensive air showers allow us to conclude that: a) the knee has an astrophysical origin; b) the 'sharpness' and the fine structure of the knee rule out 'Galactic Modulation' as the origin of the knee; c) most likely the knee is the result of the explosion of a single, recent, nearby supernova.

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A. D. Erlykin, A. W. Wolfendale. 2001-05-20. The Origin of the Knee in the Cosmic-Ray Energy Spectrum. https://arxiv.org/abs/astro-ph/0103477

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