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Search for three rare B+ ---> D+(S) X decays

This thesis presents an investigation of three rare annihilation-type B meson decays: B → D s φ, B → D s K̄◦, and B → D s K̄∗(892)◦. The analysis was performed on a sample of 84.97 million BB̄ pairs produced at the Υ(4S) resonance by the KEKB accelerator. The data was collected using the Belle detector between January 2000 and July 2002. Studies of rare B decays provide a means of testing the limits of the standard model of particle physics, beyond-standard model physics, and various phenomenological models. In this study the branching fraction measurements of these decays are compared against the minimal standard model, the Two Higgs Doublet Model (2HDM), and the R-Parity Violation model (RPV). The branching fractions of the three decays were determined to be smaller than could be measured with the available dataset, however improvements were made on the world average upper limits. The measurements are: B(B+ → D s φ) < (5.45 ± 0.58) × 10−6 B(B+ → D s K̄◦) < (3.47 ± 0.37) × 10−5 B(B+ → D s K̄∗(892)◦) < (6.08 ± 0.64) × 10−6 This thesis will show that these branching fractions are consistent with the minimal standard model. Contributions from 2HDM contributions cannot be ruled out, however RPV contributions are shown to be unlikely. The minimal standard model calculations are: B(B+ → D s φ) = (1.8 ± 0.7) × 10−6 B(B+ → D s K̄◦) = (3.0 ± 1.1) × 10−7 B(B+ → D s K̄∗(892)◦) = (1.1 ± 0.4) × 10−7