Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of Single Top Quark Production at the Tevatron Collider   On March 4, 2009, the DZero and CDF collaborations at Fermilab's Tevatron
Collider submitted papers to Physical Review Letters announcing observation of
single top quark production. This review paper describes the successful
searches carried out independently by the two collaborations, allowing the
reader to see the similarities and differences that led to the simultaneous
discoveries. Both collaborations measured a cross section
sigma(ppbar->tb+X,tqb+X) consistent with the standard model prediction at 5.0
standard deviation significance, and set a lower limit on the quark mixing
matrix element |V_tb| without assuming matrix unitarity with three quark
generations.

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The categories of this paper are: physics
31
The categories of this paper are: ao-sci
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The categories of this paper are: hep-th
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The categories of this paper are: stat
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The categories of this paper are: cs
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The categories of this paper are: math
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The categories of this paper are: hep-lat
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The categories of this paper are: cond-mat
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The categories of this paper are: atom-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin
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The categories of this paper are: eess