Branching ratio and CP asymmetry of image decays in the perturbative QCD approach Original Research Article

We calculate the branching ratios and CP-violating asymmetries for image and image decays in the perturbative QCD (pQCD) factorization approach here. We not only calculate the usual factorizable contributions, but also evaluate the non-factorizable and annihilation type contributions. Besides the current–current operators, the contributions from the QCD and electroweak penguin operators are also taken into account. The pQCD results for the CP-averaged branching ratios are image, image, and image, which agree very well with the measured values or currently available experimental upper limits. We also predict large CP-violating asymmetries in these decays: image, and image, but with large errors. The pQCD prediction for image (image) has the same (opposite) sign with the primary measured values. Further improvements in both theory and experiments are needed to clarify this discrepancy.