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تسجيل مستخدم جديدQuenched lattice calculation of the B --> D l nu decay rate
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We calculate, in the continuum limit of quenched lattice QCD, the form factor that enters in the decay rate of the semileptonic decay B --> D l nu. Making use of the step scaling method (SSM), previously introduced to handle two scale problems in lattice QCD, and of flavour twisted boundary conditions we extract G(w) at finite momentum transfer and at the physical values of the heavy quark masses. Our results can be used in order to extract the CKM matrix element Vcb by the experimental decay rate without model dependent extrapolations.
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We calculate, in the continuum limit of quenched lattice QCD, the form factor that enters the decay rate of the semileptonic decay B --> D* l nu. By using the step scaling method (SSM), previously introduced to handle two scale problems in lattice QC
D, and by adopting flavor twisted boundary conditions we extract F(w) at finite momentum transfer and at the physical values of the heavy quark masses. Our results can be used in order to extract the CKM matrix element Vcb by the experimental decay rate without model dependent extrapolations. The value of Vcb agrees with the one obtained from the B --> D l nu channel and makes us confident that the quenched approximation well applies to these transitions.
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We present a lattice QCD calculation of $Bto pi l u$ semileptonic decay form factors in the small pion recoil momentum region. The calculation is performed on a quenched $16^3 times 48$ lattice at $beta=5.9$ with the NRQCD action including the full
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