Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: JUNO: A Next Generation Reactor Antineutrino Experiment   The mass hierarchy and the CP phase are the main focus of the next generation
neutrino oscillation experiments. Jiangmen Underground Neutrino Observatory
(JUNO), as a medium baseline reactor antineutrino experiment, can determine the
neutrino mass hierarchy independent of the CP phase. The physics potential on
the mass hierarchy, and other measurements are reviewed. The preliminary design
options for a 20~kton detector with an energy resolution of
$3\%/\sqrt{E_{vis}}$ are illustrated. The main technical challenges on the PMT
and scintillator are discussed and the corresponding R\&D efforts are
presented.

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The categories of this paper are: econ
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
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The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
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The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con