Charming penguin in nonleptonic B decays

Abstract

In the study of two-body charmless B decays as a mean of looking for direct CP-violation and measuring the CKM mixing parameters in the Standard Model, the short-distance penguin contribution with its absorptive part generated by charm quark loop seems capable of producing sufficient $B \to K\pi$ decays rates, as obtained in factorization and QCD-improved factorization models. However there are also long-distance charming penguin contributions which also give rise to a strong phase due to the rescattering $D^{*}D^{*} \to K\pi$ . In this talk, I would like to discuss \cite{Isola} a recent work on the long-distance charming penguin as a a different approach to the calculation of the penguin contributions in $B \to K\pi$ decays from charmed meson intermediate states. Using chiral effective Lagrangian for light and heavy mesons, corrected for hard pion and kaon momenta, we show that the charming-penguin contributions increase significantly the $B \to K\pi$ decays rates from its short-distance contributions, giving results in better agreement with experimental data.