Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: $K_L \to \gamma \nu > \bar{\nu}$ decay beyond the standard model   The decay $K_L \to \gamma \nu \bar{\nu}$ is investigated beyond the standard
model. Interestingly, the upper limit of the CP-conserving and CP-violating
branching ratios of the decay, induced from the possible extensions of the
standard model, would be larger than the corresponding branching ratios given
in the standard model respectively, and it is expected that the CP-violating
part could be enhanced.

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The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
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The categories of this paper are: econ
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph