Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The origin of cosmic rays at all energies   There is mounting evidence from observations of long duration gamma ray
bursts (GRBs), supernova remnants (SNR) and the supernova (SN) explosion 1987A,
that SN explosions eject highly relativistic bipolar jets of plasmoids
(cannonballs) of ordinary matter. Here we use the remarkably successful
cannonball (CB) model of GRBs to show that bipolar jets from Galactic SN
explosions can produce the bulk of the Galactic cosmic rays at energies below
the ankle, while the CRs which escape into the intergalactic space or are
deposited there directly by jets from SNe in external galaxies can produce the
observed cosmic ray flux with energies above the ankle. The model predict well
all the observed properties of cosmic rays: their intensity, their spectrum
including their elemental knees and ankle, their composition and the
distribution of their arrival directions. At energies above the CR ankle, the
Galactic magnetic fields can no longer delay the free escape of such ultra high
energy CRs (UHECRs) from the Galaxy. The UHECRs, which are injected into the
intergalactic medium (IGM) by the SN jets from our Galaxy and all the other
galaxies and are isotropized there by the IGM magnetic fields, dominate the
flux of UHECRs. Almost all the extragalactic UHECRs heavier than helium
photo-disintegrate in collisions with the far infrared (FIR), microwave and
radio background radiations. The CR protons and He nuclei however suffer a
Greisen-Zatsepin-Kuzmin (GZK) cutoff due to pion photo-production in collisions
with the FIR, microwave and radio background photons.

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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
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The categories of this paper are: physics
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The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: econ
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The categories of this paper are: hep-th