Charming penguin contributions toB→Kπ

Abstract

We present calculations of the charming-penguin long-distance contributions to B→K decays due to intermediate charmed meson states. Our calculation is based on the chiral effective Lagrangian for light and heavy mesons, corrected for the hard pion and kaon momenta. We find that the charming-penguin contributions increase significantly the B→K decay rates in comparison with the short-distance contributions, giving results in better agreement with experimental data.

Charming penguin contributions inB→K*π,K(ρ,ωIsola1, Ladisa2, Nardulli3 et al. 2003Phys. Rev. D21831640View full textAdd to dashboardCite

“…However, since the residual momentum is not small we will use the complete form of the propagators instead of their approximate expressions [28,29]. The interactions among heavy and light mesons are obtained by the other three terms.…”

“…Their imaginary part can be evaluated with some confidence using the heavy meson chiral effective theory corrected for the light meson hard momenta. On the other hand, the real part is less predictable; for example in [28] and [29] the results strongly depend on the cutoff in the loop integrals.…”

“…It is evaluated by use of the effective lagrangian for light and heavy mesons based on the Heavy Quark Effective Theory (for a review see [31]). The main uncertainty of this approach is the extrapolation to hard light meson momenta and in this context we use an estimate of form factor given by us in [28]. In Section IV we present numerical results for the branching ratios and the asymmetry.…”

“…As a matter of fact the O(Λ × m −1 b ) suppression is compensated by the Cabibbo-KobayashiMaskawa enhancement and the actual role of these contributions can be established only as a result of some dynamical calculations. In [28] and [29] we estimated these contributions for the B → P P decay channels and found that for the Kπ case they are indeed relevant. Their imaginary part can be evaluated with some confidence using the heavy meson chiral effective theory corrected for the light meson hard momenta.…”

“…These are long distance contributions known in the literature as charming penguin diagrams [25,26,27,28,29,30]. Induced by the non leptonic hamiltonian ∝ V * cb V csb γ µ (1 − γ 5 )ccγ µ (1 − γ 5 )s + Fierz + h.c., they cannot contribute in the vacuum saturation approximation.…”