Long-distance effects inB→Vγradiative weak decays

Long - distance effects in B → V γ radiative weak decays

A systematic approach to long-distance effects in exclusive radiative weak B decays is presented, based on a combination of the heavy quark limit with perturbative QCD. The dominant long-distance effects, connected with weak annihilation and W-exchange topologies, can be computed in a model-independent way using experimental data on B radiative leptonic decays. Nonfactorizable corrections vanis...

Long-distance Effects in Rare K Decays

The rare K decays considered in this talk proceed through Flavor Changing Neutral Currents, arising at loop-level in the Standard Model. What makes them specially interesting is that shortdistance (SD) effects contribute significantly to their decay rates, and that long-distance (LD) hadronic effects are under theoretical control. They are thus ideal to constrain the Standard Model by precise e...

Calculation of Long-Distance Effects in Exclusive Weak Radiative Decays of B-Mesons

We calculate the contribution of the weak annihilation to the B → ργ decay amplitude by means of QCD sum rules using the photon light-cone wave function. We find that this long-distance contribution amounts to about 10% of the leading short-distance effect in B− → ρ−γ. On the other hand, weak annihilation is the dominant source of the corresponding D meson decays and according to our estimates,...

Long distance c → uγ effects in weak radiative decays of D - mesons

Long-distance effects in rare and radiative K decays

The electroweak structures of the FCNC-induced rare and radiative K decays are presented. While the former decays are sensitive to short-distance physics and offer exceptional probes for new physics, the latter are dominated by long-distance physics. Even so, they should not be set aside since they constitute essential ingredients to control the hadronic uncertainties occurring for the rare dec...