Form Factor $A_0(q^2)$, Non Leptonic $D(B) \to PV$ Transitions and Rare $B \to K^* γ$ Decays

P. Colangelo; F. De Fazio; P. Santorelli

doi:10.1103/physrevd.51.2237

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arXiv · hep-ph/9409438

Form Factor $A_0(q^2)$, Non Leptonic $D(B) \to PV$ Transitions and Rare $B \to K^* γ$ Decays

P. Colangelo·F. De Fazio·P. Santorelli

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Abstract

We use three-point function QCD sum rules to calculate the form factor $A_0(q^2)$ appearing in the matrix element of the flavour-changing axial current between the $D (B)$ state and a vector meson state. We describe the role of this form factor in nonleptonic $D (B) \to P V$ decays and analyze the light $SU(3)_F$ symmetry breaking effects. We also discuss a proposal to relate the branching ratio of $B \to K^* γ$ to the spectrum of the semileptonic $B \to ρ\ell ν$ decay.

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P. Colangelo, F. De Fazio, P. Santorelli. 1994-09-29. Form Factor $A_0(q^2)$, Non Leptonic $D(B) \to PV$ Transitions and Rare $B \to K^* γ$ Decays. https://doi.org/10.1103/physrevd.51.2237

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