Final state interaction effects in the B ⁺ → D ⁺ K ⁰ decay

Abstract

The exclusive decay of B ⁺ → D ⁺ K ⁰ is calculated by the QCD factorization method (QCDF) and final state interaction (FSI). First, the B ⁺ → D ⁺ K ⁰ decay is calculated via QCDF method. The result that is found by using the QCDF method is less than the experimental result. So FSI is considered to solve the B ⁺ → D ⁺ K ⁰ decay. For this decay, the D ⁺ _s π⁰, D ⁺ _s *ρ⁰, D ⁺ _s *ϕ via the exchange of $\bar K^0$, $\bar K^{0*}$, D ⁻, and D ⁻* mesons are chosen for the intermediate states. The above intermediate states are calculated by using the QCDF method. In the FSI effects, the results of our calculations depend on η as the phenomenological parameter. The range of this parameter is selected from 2 to 2.4. It is found that if η = 2.4 is selected, the numbers of the branching ratio are placed in the experimental range. The experimental branching ratio of this decay is less than 2.9 × 10⁻⁶ and our results calculated by QCDF and FSI are (0.16 ± 0.04) × 10⁻⁶ and (2.8 ± 0.09) × 10⁻⁶, respectively.