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Non-extensivity Effects and the Highest Energy Cosmic Ray Affair

Luis A. Anchordoqui·Diego F. Torres
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Abstract

Recent measurements of the cosmic microwave background confirm that it is described by a Planckian distribution with high precision. It is non-extensivity bounded to be less than some parts in $10^5$, or to some parts in $10^4$ at most. This deviation may appear minuscule, but may have a non-negligible effect on a particle propagating through this background over the course of millions of years. In this paper we analyze the possible influence of such a slight deviation upon the propagation of nuclei and protons of ultra-high energy. These particles interact via photopion and photodisintegration processes which we examine taking into account a slight non-extensive background. We show that such a deviation does not exhibit a significant difference in the energy attenuation length of extremely high energy cosmic rays.

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Luis A. Anchordoqui, Diego F. Torres. 2001-04-17. Non-extensivity Effects and the Highest Energy Cosmic Ray Affair. https://doi.org/10.1016/s0375-9601(01)00256-0

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