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We study the branching ratios, the direct CP asymmetries in B → K ( * )K ( * ) decays and the polarization fractions of B → K * K * decays by employing the QCD factorization in the minimal supersymmetric standard model with R-parity violation. We derive the new upper bounds on the relevant R-parity violating couplings from the latest experimental data of B → K ( * )K ( * ) , and some of these constraints are stronger than the existing bounds. Using the constrained parameter spaces, we predict the R-parity violating effects on the other quantities in B → K ( * )K ( * ) decays which have not been measured yet.We find that the R-parity violating effects on the branching ratios and the direct CP asymmetries could be large, nevertheless their effects on the longitudinal polarizations of B → K * K * decays are small. Near future experiments can test these predictions and shrink the parameter spaces.

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In this paper, we studied the semileptonic decays B → D ( * ) l −ν l by using the "pQCD+Lattice QCD" method. We made the extrapolation for the six relevant form factors by using the input values obtained from the pQCD factorization approach in the low q 2 region of 0 ≤ q 2 ≤ m 2 τ , and the Lattice QCD input at the end-point q 2 = q 2 max . We then calculated the ratios R(D) and R(D * ) of the branching ratios B(B → D ( * ) l −ν l ), and found numerically that (1) the "pQCD+Lattice QCD" predictions for the branching ratios B(B → D ( * ) l −ν l ) agree well with the measured values within one standard deviation; and (2)

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