Comment on Vub from Exclusive Semileptonic B and D Decays
نویسندگان
چکیده
The prospects for determining |Vub| from exclusive B semileptonic decay are discussed. The double ratio of form factors (f (B→ρ)/f (B→K ∗))/ (f (D→ρ)/f (D→K ∗)) is calculated using chiral perturbation theory. Its deviation from unity due to contributions that are non-analytic in the symmetry breaking parameters is very small. Combining experimental data obtainable from B → ρ l ν̄l, B → Kl l̄ and D → ρ l̄ νl can lead to a model independent determination of |Vub| with an uncertainty from theory of about 10%.
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