Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of Tau Neutrino Appearance and Recent Results from OPERA   The OPERA experiment was designed to observe ${\nu_{\mu}}$ ${\rightarrow}$
${\nu_{\tau}}$ oscillations through ${\nu_{\tau}}$ appearance at a baseline of
730 km in the CNGS beam. Newly developed emulsion analysis technology allows to
measure ${\nu_e}$, ${\nu_{\mu}}$ and ${\nu_{\tau}}$ interactions with the
largest emulsion detector ever made. OPERA has detected five ${\nu_{\tau}}$
candidates, allowing to reject the background-only hypothesis at 5.1
${\sigma}$. The parameters for standard and non-standard oscillations are
measured and constrained.

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The categories of this paper are: supr-con
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The categories of this paper are: acc-phys
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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: funct-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: econ
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The categories of this paper are: hep-th
1
The categories of this paper are: cs
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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: nucl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: math
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The categories of this paper are: alg-geom