Related papers: Towards NNLO corrections in B --> D pi
We calculate the complete NNLO QCD corrections to the charm contribution of the rare decay K+ -> pi+ nu nu-bar. We encounter several new features, which were absent in lower orders. We discuss them in detail and present the results for the…
We compute the differential and total rate of the semileptonic decay of polarized top-quarks $t\to \ell \nu_\ell + b{\rm jet} + {\rm jet}$ at next-to-leading order (NLO) in the QCD coupling with an off-shell intermediate $W$ boson. We…
The branching fractions of the rare weak $B\to \pi l^+l^-(\nu\bar\nu)$ and $B\to\rho l^+l^-(\nu\bar\nu)$ decays are calculated in the framework of the relativistic quark model based on the quasipotential approach. The form factors…
The perturbative QCD (PQCD) approach based on $k_T$ factorization has made a great achievement for the QCD calculation of the hadronic B decays. Regulating the endpoint divergence by the transverse momentum of quarks in the propagators, one…
We introduce a new technique to calculate perturbative corrections to neutron-deuteron ($nd$) scattering that does not require calculation of the full off-shell scattering amplitude. Its relation to the more familiar partial-resummation…
In this note, we calculate the branching ratio of B_c\to J/\psi K in the framework of perturbative QCD approach based on k_T factorization. This decay can occur only via tree level diagrams in the Standard Model. We find that the branching…
We apply the QCD factorization approach to exclusive, radiative B meson decays in the region of small invariant photon mass. We calculate factorizable and non-factorizable corrections to leading order in the heavy quark mass expansion and…
We briefly review a subtraction scheme for computing radiative corrections to QCD jet cross sections that can be defined at any order in perturbation theory. Hereafter we discuss the computational methods used to evaluate analytically and…
For the color-suppressed $\bar{B}^0\longrightarrow D^{0}\pi^{0}$ decay, nonfactorizable contributions are expected to be leading and naive factorization description breaks down. We estimate $1/m_b$ power-suppressed nonfactorizable effect in…
We report preliminary results of an experimental investigation of the color-suppressed decays bar{B^0} --> D^0 pi^0, D^0 eta, and D^0 omega. We measure the branching fractions B (bar{B^0} --> D^0 pi^0) = (2.89 +/- 0.29 (stat.) +/- 0.38…
We study quantitatively the importance of the recently derived NLO corrections to the DIS structure functions at small x in the dipole formalism. We show that these corrections can be significant and depend on the factorization scheme used…
We present a calculation of next-to-leading-order (NLO) QCD corrections to total hadronic production cross sections and to light-hadron-decay rates of heavy quarkonium states. Both colour-singlet and colour-octet contributions are included.…
We report on recent theoretical progress in radiative B decays. We focus on a calculation of logarithmically enhanced QED corrections to the branching ratio and forward-backward asymmetry in the inclusive rare decay anti-B --> X(s) l+ l-,…
We provide updated predictions for the hadronic decays $\bar{B}_s^0\to D_s^{(*)+} \pi^-$ and $\bar{B}^0\to D^{(*)+} K^-$. They are based on $\mathcal{O}(\alpha_s^2)$ results for the QCD factorization amplitudes at leading power and on…
Power corrections seem to play an important role in charmless B decays as indicated by recent analysis using QCD Factorization. In this talk, I would like to report on a recent work on power corrections in charmless B decays. By using the…
We calculated the CP averaged branching ratios and CP-violating asymmetries of two-body charmless hadronic Bs->PP,PV decays with the QCDF approach, including the contributions from the chirally enhanced power corrections and weak…
Though QCD Factorization(QCDF) could produce sufficiently large $B\to K\pi$ branching ratios close to experiments, the predicted direct CP asymmetry in ${\bar B}^{0}\to K^{+}\pi^{-}$ decay is however still quite below experiment, even with…
The ${\Upsilon}(nS)$ ${\to}$ $B_{c}D_{s}$, $B_{c}D_{d}$ weak decays are studied with the pQCD approach firstly. It is found that branching ratios ${\cal B}r({\Upsilon}(nS){\to}B_{c}D_{s})$ ${\sim}$ ${\cal O}(10^{-10})$ and ${\cal…
We have computed the complete next-to-next-to-leading order (NNLO) contributions to the splitting functions governing the evolution of unpolarized parton densities in perturbative QCD. Our results agree with all partial results available in…
We discuss the theory prediction of epsilon_K and the rare K -> pi nu nu-bar decays and review the structure and current status of higher-order contributions to these flavour changing processes in the standard model in some detail. This…