相关论文: $B$ meson mixing at NNLO: technical aspects
In the heavy quark limit, the form factors for semileptonic and rare radiative B decays into light mesons are related by heavy quark spin symmetry. Here we compute the leading corrections of order \Lambda/m_Q to these symmetry relations,…
Measurement of the $B^0_s$ oscillation frequency via $B^0_s$ mixing analysis provides a powerful constraint on CKM matrix elements. This note briefly reviews the motivation behind these analyses and describes the various steps that go into…
We review and update the branching ratios for the $B \to (\rho,\omega) \gamma$ decays, calculated in the QCD factorization approach in the next-to-leading order (NLO) in the strong coupling $\alpha_s$ and to leading power in $\Lambda_{\rm…
In this talk the application of the recently introduced methods to merge NLO calculations of successive jet multiplicities to the production of top pairs in association with jets will be discussed, in particular a fresh look is taken at the…
I present a unified calculation of soft-gluon corrections to hard-scattering cross sections through next-to-next-to-next-to-leading order (NNNLO). Master formulas are derived, from a threshold resummation formalism, that can be applied to…
The measurement and precision at B physics experiment are reviewed by taking into account of the numbers of B mesons to be produced in the future experimental projects. With $10^9$ or more B mesons we will be able to fix the parameters in…
The paper deals with a next-to-leading order analysis of the radiative $B \to K^* \gamma$ decay. Working in a PQCD approach, we compute the correction to the essential form factor, coming from a single gluon exchange with the spectator. We…
We compute the perturbative corrections to the HQET sum rules for the matrix element of the \Delta B=2 operator that determines the mass shift of $B^0$, $\bar{B}^0$ states. Technically, we obtain analytically the non-factorizable…
Events with observed D* and/or muons in the final state were used to indicate the presence of beauty quark production and to study the correlations between the particles coming from the same or different B-hadrons. The Next-to-Leading Order…
We briefly summarize the current status of perturbative calculations at next-to-next-to-leading-order (NNLO) accuracy in the \bar{B}\to X_s\gamma decay rate as well as that of non-perturbative power-corrections.
The LHC provides new opportunities to improve our understanding of the b quark using high statistics data samples and the 14 TeV center-of-mass energy. The prospects to measure the cross section for inclusive b production in events…
We demonstrate a method for calculating the neutral B-meson decay constants and mixing matrix elements in unquenched lattice QCD with domain-wall light quarks and static b-quarks. Our computation is performed on the "2+1" flavor gauge…
We firstly address the recent efforts on calculations of the next-to-leading order corrections to the color-suppressed tree amplitude in QCD factorization method which may be essential to solve the puzzles in $B\to \pi\pi$ and $\pi K$…
The inclusive decay B --> X_u l nu is of much interest because of its potential to constrain the CKM element |V_ub|. Experimental cuts required to suppress charm background restrict measurements of this decay to the shape-function region,…
Details of a recent calculation of O(alpha_s^2) corrections to the decay b -> c,l,nu_l, taking into account the c-quark mass, are described. Construction of the expansion in the mass ratio m_c/m_b as well as the evaluation of new four-loop…
Current status of the computation of the neutral B-meson mixing amplitudes, with particular attention to the heavy-light meson decay constants, is reviewed. The values for these quantities, as well as for the coupling of the pion to the…
The most recent b-physics results from the OPAL experiment at LEP are reviewed. A measurement of semileptonic B meson decays to narrow orbitally-excited charm mesons is presented first, followed by a study of charm production in b-hadron…
We present a complete next-to-leading-order calculation of the QCD corrections to $B^0-\bar{B}^0$ ($K^0-\bar{K}^0$) mixing in the framework of the minimal flavor violating (MFV) supersymmetry. We take into account the contributions from the…
We present the status of our calculation of hadronic matrix elements for $D$- and $B$-meson mixing. We use a large set of the MILC collaboration's $N_f=2+1$ asqtad ensembles, which includes lattice spacings in the range $a\approx0.12$-0.045…
The production of four bottom quarks is an important benchmark channel for Higgs analyses and searches for new physics at the LHC. We report on the calculation of the next-to-leading order QCD corrections to the process pp -> b anti-b b…