Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evidence for the Rare Decay B+ --> Ds+ pi0   We have searched for the rare decay B+ --> Ds+ pi0. The analysis is based on
a sample of 232 million Upsilon(4S) --> B anti-B decays collected with the
BABAR detector at the PEP-II e+ e- storage ring. We find 19.6 signal events,
corresponding to a significance of 4.7 sigma. The extracted signal yield
including statistical and systematic uncertainties is 20.1+6.8+0.4 -6.0-1.5,
and we measure B(B+ --> Ds+ pi0) =(1.5 +0.5 -0.4 +- 0.1 +- 0.2) 10^-5, where
the first uncertainty is statistical, the second is systematic, and the last is
due to the uncertainty on the Ds+ decay and its daughter decay branching
fractions.

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The categories of this paper are: nucl-ex
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The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
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The categories of this paper are: eess
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The categories of this paper are: econ
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
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The categories of this paper are: cs
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The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat