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Fluxes of cosmic rays: A delicately balanced stationary state

Constantino Tsallis·Joao C. Anjos·Ernesto P. Borges
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Abstract

The analysis of cosmic rays fluxes as a function of energy reveals a {\it knee} slightly below $10^{16}$ eV and an {\it ankle} close to $10^{19}$ eV. Their physical origins remain up to now quite enigmatic; in particular, no elementary process is known which occurs at energies close to $10^{16}$ eV. We propose a phenomenological approach along the lines of nonextensive statistical mechanics, a formalism which contains Boltzmann-Gibbs statistical mechanics as a particular case. The knee then appears as a crossover between two fractal-like thermal regimes, the crossover being caused by process occurring at energies ten million times lower than that of the knee, in the region of the quark hadron transition ($\simeq 10^{9}$ eV). This opens the door to an unexpected standpoint for further clarifying the phenomenon.

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Constantino Tsallis, Joao C. Anjos, Ernesto P. Borges. 2004-04-03. Fluxes of cosmic rays: A delicately balanced stationary state. https://doi.org/10.1016/s0375-9601(03)00377-3

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