Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Search for Theta+ via pi- p --> K- X reaction near production threshold   We have searched for $\Theta^{+}$ via $\pi^{-}p \to K^{-}X$ reaction using
1.87 and 1.92 GeV/c $\pi^{-}$ beam at the K2 beam line of the KEK 12 GeV Proton
Synchrotron. In the missing mass spectrum at beam momentum of 1.92 GeV/$c$, a
bump has been found at 1530 MeV/$c^{2}$ which is consistent with the mass
reported by several experiments. The statistical significance of this bump,
however, is only 2.5$-2.7\sigma$. Therefore we have derived the upper limit of
$\Theta^{+}$ production cross section via $\pi^{-}p \to K^{-}\Theta^{+}$
reaction which is 4.3$\mu$b at 90% confidence level assuming that $\Theta^{+}$
is produced isotropically in the center of mass system.

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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
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The categories of this paper are: econ
12
The categories of this paper are: nucl-th
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The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: quant-ph
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The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: physics