Subleading Shape Functions and the Determination of |v Ub |
نویسنده
چکیده
It is argued that the dominant subleading shape-function contributions to the endpoint region of the charged-lepton energy spectrum in B → Xu l ν decays can be related in a model-independent way to an integral over the B → Xsγ photon spectrum. The square of the fraction of B → Xu l ν events with charged-lepton energy above E0 = 2.2GeV can be calculated with a residual theoretical uncertainty from subleading shape-function effects that it safely below the 10% level. These effects have therefore a minor impact on the determination of |Vub|.
منابع مشابه
Subleading Shape Functions and the Determination
It is argued that the dominant subleading shape-function contributions to the endpoint region of the charged-lepton energy spectrum in B → Xu l ν decays can be related in a model-independent way to an integral over the B → Xsγ photon spectrum. The square root of the fraction of B → Xu l ν events with chargedlepton energy above E0 = 2.2GeV can be calculated with a residual theoretical uncertaint...
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