Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Searches for Large-Scale Anisotropy in the Arrival Directions of Cosmic
  Rays Detected above Energy of $10^{19}$ eV at the Pierre Auger Observatory
  and the Telescope Array   Spherical harmonic moments are well-suited for capturing anisotropy at any
scale in the flux of cosmic rays. An unambiguous measurement of the full set of
spherical harmonic coefficients requires full-sky coverage. This can be
achieved by combining data from observatories located in both the northern and
southern hemispheres. To this end, a joint analysis using data recorded at the
Telescope Array and the Pierre Auger Observatory above $10^{19}$ eV is
presented in this work. The resulting multipolar expansion of the flux of
cosmic rays allows us to perform a series of anisotropy searches, and in
particular to report on the angular power spectrum of cosmic rays above
$10^{19}$ eV. No significant deviation from isotropic expectations is found
throughout the analyses performed. Upper limits on the amplitudes of the dipole
and quadrupole moments are derived as a function of the direction in the sky,
varying between 7% and 13% for the dipole and between 7% and 10% for a
symmetric quadrupole.

21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
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The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
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The categories of this paper are: solv-int
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The categories of this paper are: bayes-an
1
The categories of this paper are: cs
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The categories of this paper are: eess
5
The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: plasm-ph
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The categories of this paper are: quant-ph
2
The categories of this paper are: math
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The categories of this paper are: nucl-ex