Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Study of B^+/- --> J/psi pi^+/- and B^+/- --> J/psi K^+/- Decays:
  Measurement of the Ratio of Branching Fractions and Search for Direct CP
  Violation   We study B^+/- --> J/psi pi^+/- and B^+/- --> J/psi K^+/- decays in a sample
of about 89 million BB~ pairs collected with the BABAR detector at the PEP-II
asymmetric B-factory at SLAC. We observe a signal of 244 +/- 20 B^+/- --> J/psi
pi^+/- events and determine the ratio BF(B^+/- --> J/psi pi^+/-)/BF(B^+/- -->
J/psi K^+/-) to be [5.37 +/- 0.45 (stat.) +/- 0.11 (syst)]%. The charge
asymmetries for the B^+/- --> J/psi pi^+/- and B^+/- --> J/psi K^+/- decays are
determined to be A_pi = 0.123 +/- 0.085 (stat.) +/- 0.004 (syst.) and A_K =
0.030 +/- 0.015 (stat.) +/- 0.006 (syst.), respectively.

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The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
2
The categories of this paper are: math
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The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
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The categories of this paper are: nlin
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The categories of this paper are: nucl-th
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The categories of this paper are: adap-org
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The categories of this paper are: chem-ph