Exclusive B → Mℓ + ℓ − (M = π, K, ρ, K ∗ ) Decays and Determinations of |Vts | (and |Vtd/Vts|)
نویسنده
چکیده
We examine the possibility for precise determination of |Vts| (and |Vtd/Vts|) from the exclusive decays, B → Kl+l−, B → K∗l+l− (and B → πl+l−, B → ρl+l−). We show that the ratio |Vts| can be extracted experimentally with a small theoretical uncertainty from hadronic form–factors, if we appropriately constrain kinematical regions of q2. We also give detailed analytical and numerical results on the differential decay width dΓ(B → K∗l+l−)/dq2, and the ratios of integrated branching fractions, B(B → ρl+l−)/B(B → K∗l+l−). We estimate that one can determine the ratio |Vts| from those decays within theoretical accuracy of ∼ 10%. [email protected] [email protected], http://phya.yonsei.ac.kr/ ̃cskim/ [email protected] 1
منابع مشابه
Exclusive B → Mℓ + ℓ − (M = π, K, ρ, K ∗ ) Decays and Determinations of |Vts | and/or |Vtd/Vts|
We examine the possibility for precise determination of |Vtd| and/or |Vtd/Vts| from the ratios of exclusive decays, (B → ρl+l−)/(B → K∗l+l−) and (B → πl+l−)/(B → Kl+l−). We show that the ratio |Vtd/Vts| can be extracted experimentally with a small theoretical uncertainty from SU(3) breaking effects and hadronic form–factors, if we appropriately constrain kinematical regions of q2. We also give ...
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