Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exotic Neutrino Interactions in Cosmic Rays   The spectrum of extra-galactic cosmic rays (CRs) is expected to follow the
Greisen-Zatsepin-Kuzmin (GZK) cutoff at about 5x10^10 GeV which results from
energy losses of charged nuclei in the cosmic microwave background. So far the
confrontation of this feature with CR data is inconclusive. In the absence of
close-by sources a power-law continuation of the spectrum might signal the
contribution of new physics. We have investigated the statistical significance
of a model where exotic interactions of cosmogenic neutrinos are the origin of
super-GZK events. A strong neutrino-nucleon interaction is favored by CR data,
even if we account for a systematic shift in energy calibration.

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The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg