Fat penguins and imaginary penguins in perturbative QCD

We evaluate B→Kπ decay amplitudes in perturbative QCD picture. It is found that penguin contributions are dynamically enhanced by nearly 50% compared to those assumed in the factorization approximation. It is also shown that annihilation diagrams are not negligible, and give large strong phases. Our results for branching ratios of B→Kπ decays for a representative parameter set are consistent with data.