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On the viability of holistic cosmic-ray source models

J. Aublin·E. Parizot
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Abstract

We consider the energy spectrum of cosmic-rays (CRs) from a purely phenomenological point of view and investigate the possibility that they all be produced by the same type of sources with a single power-law spectrum, in E^{-x}, from thermal to ultra-high energies. We show that the relative fluxes of the Galactic (GCR) and extra-galactic (EGCR) components are compatible with such a holistic model, provided that the index of the source spectrum be x \simeq 2.23\pm 0.07. This is compatible with the best-fit indices for both GCRs and EGCRs, assuming that their source composition is the same, which is indeed the case in a holistic model. It is also compatible with theoretical expectations for particle acceleration at relativistic shocks.

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J. Aublin, E. Parizot. 2006-05-01. On the viability of holistic cosmic-ray source models. https://doi.org/10.1051/0004-6361%3A20065293

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