The Rare Decay B → K ∗ γ : A More Precise Calculation
نویسنده
چکیده
Efforts to predict the rare exclusive decay B → Kγ from the well known inclusive decay b → sγ are frustrated by the effect of the large recoil momentum. We show how to reduce the large uncertainty in calculating this decay by relating B → Kγ to the semileptonic process B → ρeν̄ using the heavy-quark symmetry in B decays and SU(3) flavor symmetry. A direct measurement of the q-spectrum for the semileptonic decay can provide accurate information for the exclusive rare decay.
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