Towards B → V γ Decays at NNLO in SCET
نویسندگان
چکیده
We compute NNLO (O(α2 s)) corrections to the hard-scattering kernels entering the QCD factorization formula for B → V γ decays, where V is a light vector meson. We give complete NNLO results for the dipole operators Q7 and Q8, and partial results for Q1 valid in the large-β0 limit and neglecting the NNLO correction from hard spectator scattering. Large perturbative logarithms in the hard-scattering kernels are identified and resummed using soft-collinear effective theory. We use our results to estimate the branching fractions for B → Kγ and Bs → φγ decays at NNLO and compare them with the current experimental data. E-mail: [email protected] E-mail: [email protected] Email: [email protected]
منابع مشابه
Decays at NNLO in SCET
We compute NNLO (O(α2 s)) corrections to the hard-scattering kernels entering the QCD factorization formula for B → V γ decays, where V is a light vector meson. We give complete NNLO results for the dipole operators Q7 and Q8, and partial results for Q1 valid in the large-β0 limit and neglecting the NNLO correction from hard spectator scattering. Large perturbative logarithms in the hard-scatte...
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