相关论文: Multi-parton contributions to $\bar B \to X_s \gam…
We report on the status of the ongoing calculation of multiparticle contributions to the inclusive radiative $\bar{B} \rightarrow X_s \gamma$ decay at next-to leading order. This effort amounts to the evaluation of the four-particle process…
Ongoing efforts to reduce the perturbative uncertainty in the B -> Xs gamma decay rate have resulted in a theory estimate to NNLO in QCD. However, a few contributions from multi-parton final states which are formally NLO are still unknown.…
In this short review, the calculation of the next-to-next-to-leading order QCD corrections to the inclusive radiative decay B -> X_s gamma is described. I summarize the salient features of the calculational framework adopted, discuss the…
We briefly discuss the status of the NNLL QCD calculations in the inclusive rare B decay $B \to X_s \ell^+ \ell^-$. Two important ingredients, the two-loop matrix elements of the four quark operator ${\cal O}_2$ and the bremsstrahlung…
We give a summary about the various contributions which have to be calculated in order to obtain the next-to-leading logarithmic result for the branching ratio $BR(B \to X_s \gamma)$. Combining all these ingredients, which were obtained by…
The theoretical status of NNLO QCD corrections to the inclusive radiative anti-B -> X_s gamma decay in the standard model is briefly overviewed. Emphasis is put on recent results for three-loop fermionic corrections to matrix elements of…
We calculate tree-level contributions to the inclusive rare $\bar B \to X_{s(d)} \, \ell^+\ell^-$ decays. At the partonic level they stem from the five-particle process $b \to s(d) \, q \bar q \, \ell^+\ell^-$, with $q \in \{u,d,s\}$. While…
In this paper, we calculated the next-to-leading order (NLO) new physics contributions to the mass splitting $\dmd$ and the branching ratio $\brbxsga$ induced by the charged Higgs loop diagrams in the third type of two-Higgs-doublet models…
The experimental and theoretical status of the inclusive decay B -> X_s gamma is briefly summarized. Results from a very recent theoretical analysis are reported. An ~11% increase in the SM prediction for BR[ B -> X_s gamma] is found after…
We compute the next-to-next-to-leading order (NNLO) QCD corrections to b \to c l \bar \nu_l decay rate at a fully differential level. Arbitrary cuts on kinematic variables of the decay products can be imposed. Our computation can be used to…
We present a concise review of the recent theoretical progress concerning the standard model calculation of the inclusive radiative Bbar -> X_s gamma decay. Particular attention is thereby devoted to the calculations of the…
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.
We report on progress towards including next-to-leading order (NLO) radiative corrections to the subleading-power factorization formula for the $Q_1^{q}-Q_{7\gamma}$ interference contribution in $\bar{B}\to X_s\gamma$ at large photon…
The calculation of NLO QCD corrections to the production cross section of two bottom pairs at the LHC is briefly summarized. We describe the pp -> b anti-b b anti-b+X process both in the 4-flavor and 5-flavor scheme and investigate the…
By combining a recent estimate of the total B-->X_s gamma branching fraction at O(alpha_s^2) with a detailed analysis of the effects of a cut E_gamma>1.6GeV on photon energy, a prediction for the partial B-->X_s gamma branching fraction at…
We discuss nonperturbative contributions to the inclusive rare $B$ decays $B\to X_s\gamma$ and $B\to X_s\ell^+\ell^-$. We employ an operator product expansion and the heavy quark effective theory to compute the leading corrections to the…
By employing the perturbative QCD(pQCD) factorization approach, we calculate the branching ratios and CP violating asymmetries of the four $\bar{B}_s^0 \to K\pi$ and $K K $ decays, with the inclusion of all known next-to-leading order (NLO)…
The current status of B -> Xs gamma decay rate calculations is summarized. Missing ingredients at the NNLO level are listed. The global normalization factor and non-perturbative effects are discussed. Arguments are presented that results…
I review the NLO QCD calculations of the branching ratio for B--> X_s gamma in the SM. Including the leading electromagnetic corrections, one obtaines BR(B-> X_s gamma)=(3.32 +- 0.30)*10^{-4}. Confronting theory with the newest data, an…
The Higgs boson pair production at the LHC provides a probe to the Higgs boson self-coupling. The higher-order QCD corrections in this process are sizable and must be taken into account in comparison with data. Due to the small cross…