Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Radio detection of cosmic rays in the Pierre Auger Observatory   In small-scale experiments such as CODALEMA and LOPES, radio detection of
cosmic rays has demonstrated its potential as a technique for cosmic ray
measurements up to the highest energies. Radio detection promises measurements
with high duty-cycle, allows a direction reconstruction with very good angular
resolution, and provides complementary information on energy and nature of the
cosmic ray primaries with respect to particle detectors at ground and
fluorescence telescopes. Within the Pierre Auger Observatory, we tackle the
technological and scientific challenges for an application of the radio
detection technique on large scales. Here, we report on the results obtained so
far using the Southern Auger site and the plans for an engineering array of
radio detectors covering an area of ~20 km^2.

25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ