2002/03/31 by Constantino Tsallis, Joao C. Anjos, João C. dos Anjos +1 · 6 citations
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Cosmology and Gravitation Theories #Statistical Mechanics and Entropy #astro-ph #cond-mat
paper · pdf · doi:10.1016/s0375-9601(03)00377-3
published as Phys.Lett. A310 (2003) 372 · RevTeX, 10 pages including 1 eps figure
openalex publication_date 2003/04/01 · arxiv created 2004/04/03 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The analysis of cosmic rays fluxes as a function of energy reveals a knee slightly below 1016 eV and an ankle close to 1019 eV. Their physical origins remain up to now quite enigmatic; in particular, no elementary process is known which occurs at energies close to 1016 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 (≃109 eV). This opens the door to an unexpected standpoint for further clarifying the phenomenon.