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Top-Down Models and Extremely High Energy Cosmic Rays

O. E. Kalashev·V. A. Kuzmin·D. V. Semikoz
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Abstract

We developed numerical code for calculation of the extragalactic component of the spectra of leptons, nucleons and $γ$-rays resulting from ``top-down'' (non-acceleration) models for the case of uniform and isotropic source distribution. We explored two different classes of ``top-down'' scenarios: the wide earlier investigated class of X particles coming from collapse and/or annihilation of cosmic topological defects (such as cosmic strings, monopoles, etc.) and the models of super-heavy long-living X particles with lifetime of the order or much greater than the current Universe age.

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O. E. Kalashev, V. A. Kuzmin, D. V. Semikoz. 1999-12-01. Top-Down Models and Extremely High Energy Cosmic Rays. https://arxiv.org/abs/astro-ph/9911035

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