Peter L. Biermann, Vitor de Souza
The origin of cosmic rays at all energies is still uncertain. In this paper
we present and explore an astrophysical scenario to produce cosmic rays with
energy ranging from below $10^{15}$ o $3 \times 10^{20}$ eV. We show here that
just our Galaxy and the radio galaxy Cen A, each with their own galactic cosmic
ray particles, but with those from the radio galaxy pushed up in energy by a
relativistic shock in the jet emanating from the active black hole, are
sufficient to describe the most recent data in the energy range PeV to near
ZeV. Data are available over this entire energy range from the experiments
KASCADE, KASCADE-Grande and Pierre Auger Observatory. The energy spectrum
calculated here correctly reproduces the measured spectrum beyond the knee, and
contrary to widely held expectations, no other extragalactic source population
is required to explain the data, even at energies far below the general cutoff
expected at $6 \times 10^{19}$ eV, the Greisen-Zatsepin-Kuzmin turn-off due to
interaction with the cosmological microwave background. We present several
predictions for the source population, the cosmic ray composition and the
propagation to Earth which can be tested in the near future.
View original:
http://arxiv.org/abs/1106.0625
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