Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Rare Decay of K Meson   We investigate the rare decay processes of the K mesons, K_{L,S} -> \pi^0 \nu
\bar{\nu} and K^{+} -> \pi^+ \nu \bar{\nu} in LR model with lepton family
number being well conserved. In these processes, scalar operators
(\bar{s}d)(\bar{\nu}_{\tau}\nu_{\tau}), which are derived from box diagram in
LR model, play an important role due to an enhancement factor M_{K}/m_{s} in
the matrix element $<\pi|\bar{s}d|K>$. It is emphasized that the K_{L} decay
process through the scalar operator is not the CP violating mode, so the B(K_L
-> \pi^{0} \nu \bar{\nu}) remains non-zero even in the CP conserved limit. We
present the pion energy spectrum for these processes and discuss the effects of
LR model.

2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
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The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom