High Energy Cosmic Rays and Baryonic Fraction of the Universe

H. Ziaeepour

European Southern Observatory \\Schwarzchild strasse, 2, 85748, Garching b. M\"{u}nchen, Germany


The origin of High Energy Cosmic Rays (HECR) with energies around and beyond the Greisen-Zatsepin-Kuz'min expected cut off is not yet fully understood. One of the candidates is the decay of heavy particles or defects (vortexes) with a mass close to the GUT scale. These species are also potential candidates for dark matter (DM).

We study the effect of very slow decay of these types of dark matter on the evolution of baryonic fraction of the universe and high energy backgrounds. We assume that these heavy (pseudo-)particles make the dominant part of the DM. The evolution of the fraction of different components in presence of fluctuations is simulated by solving Einstein-Boltzman equations with linear approximation. The Boltzman equation includes perturbative and non-perturbative important interactions from high energies up to a few eV for protons.

In this poster we present the formalism and methodology of this calculation and some perlimianry results.


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