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A study of B^+/- --> J/psi pi^+/- and B^+/- --> J/psi K^+/- decays: measurement of the ratio of branching fractions and search for direct CP-violating charge asymmetries

B. Aubert
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Abstract

We have studied the B^+/- --> J/psi pi^+/- and B^+/- --> J/psi K^+/- decays using a 20.7 fb-1 data set collected with the BABAR detector. We observe a signal of 51+/-10 B^+/- --> J/psi pi^+/- events and determine the ratio BF(B^+/- --> J/psi pi^+/-)/BF(B^+/- --> J/psi K^+/-) to be [3.91 +/- 0.78 (stat.) +/- 0.19 (syst.)]%. The CP-violating charge asymmetries for the B^+/- --> J/psi pi^+/- and B^+/- --> J/psi K^+/- decays are determined to be A_pi = 0.01 +/- 0.22 (stat.) +/- 0.01 (syst.) and A_K = 0.003 +/- 0.030 (stat.) +/- 0.004 (syst.).

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B. Aubert. 2002-04-04. A study of B^+/- --> J/psi pi^+/- and B^+/- --> J/psi K^+/- decays: measurement of the ratio of branching fractions and search for direct CP-violating charge asymmetries. https://doi.org/10.1103/physrevd.65.091101

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