Towards a next-to-leading logarithmic result in B → Xsγ a
نویسنده
چکیده
The calculation of the O(αs) virtual corrections to the matrix element of the inclusive decay b → sγ is reported. These contributions drastically reduce the large renormalization scale dependence of the leading logarithmic calculation. Combining these results with the preliminary result for the Wilson coefficient C7(mb) calculated recently by Chetyrkin, Misiak, and Münz, we estimate the branching ratio to be BR(B → Xsγ) = (3.25± 0.50) × 10.
منابع مشابه
Towards a next-to-leading logarithmic result in B → Xsγ, SLACPUB-7267, ITP-SB-96-46, hep-ph/9608449; M. Misiak, talk given at 28th Int
The calculation of the O(αs) virtual corrections to the matrix element of the inclusive decay b → sγ is reported. These contributions drastically reduce the large renormalization scale dependence of the leading logarithmic calculation. Combining these results with the preliminary result for the Wilson coefficient C 7 (m b) calculated recently by Chetyrkin, Misiak, and Münz, we estimate the bran...
متن کاملB̄ → X s γ : Standard Model and Beyond †
We present a concise review of the recent theoretical progress concerning the standard model calculation of the inclusive radiative B̄ → Xsγ decay. Particular attention is thereby devoted to the calculations of the next-to-next-to-leading order fixed-order O(αs) contributions, non-local O(αsΛ/mb) power corrections, and logarithmic-enhanced O(αs) cut-effects to the decay rate. The current status ...
متن کاملTaming the B̄ −→ Xsγ spectrum by Dressed Gluon Exponentiation
We show that the B̄ −→ Xsγ photon energy (Eγ) spectrum can be reliably computed by resummed perturbation theory. Our calculation is based on Dressed Gluon Exponentiation (DGE) incorporating Sudakov and renormalon resummation. It is shown that the resummed spectrum does not have the perturbative support properties: it smoothly extends to the non-perturbative region Eγ > m/2, where m is the quark ...
متن کاملQuark mass effects in B̄ → X s γ
The charm-loop contribution to B̄ → Xsγ is found to be numerically dominant and very stable under logarithmic QCD corrections. The strong enhancement of the branching ratio by QCD logarithms is mainly due to the b-quark mass evolution in the top-quark sector. These observations allow us to achieve better control over residual scale-dependence at the next-to-leading order. Furthermore, we observe...
متن کاملRenormalization - Group Improved Calculation of the B → X s γ Branching Ratio
Using results on soft-collinear factorization for inclusive B-meson decay distributions, a systematic study of the partial B → Xsγ decay rate with a cut Eγ ≥ E0 on photon energy is performed. For values of E0 below about 1.9GeV, the rate can be calculated without reference to shape functions using a multi-scale operator product expansion (MSOPE). The transition from the shape-function region to...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1996