Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: CRPropa 3 - a Public Astrophysical Simulation Framework for Propagating
  Extraterrestrial Ultra-High Energy Particles   We present the simulation framework CRPropa version 3 designed for efficient
development of astrophysical predictions for ultra-high energy particles. Users
can assemble modules of the most relevant propagation effects in galactic and
extragalactic space, include their own physics modules with new features, and
receive on output primary and secondary cosmic messengers including nuclei,
neutrinos and photons. In extension to the propagation physics contained in a
previous CRPropa version, the new version facilitates high-performance
computing and comprises new physical features such as an interface for galactic
propagation using lensing techniques, an improved photonuclear interaction
calculation, and propagation in time dependent environments to take into
account cosmic evolution effects in anisotropy studies and variable sources.
First applications using highlighted features are presented as well.

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The categories of this paper are: atom-ph
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The categories of this paper are: supr-con
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The categories of this paper are: cs
0
The categories of this paper are: hep-ph
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The categories of this paper are: physics
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The categories of this paper are: eess
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The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
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The categories of this paper are: econ
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The categories of this paper are: math-ph
2
The categories of this paper are: math
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The categories of this paper are: funct-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-bio
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin