Related papers: Threshold resummation for nonleptonic B meson deca…
We calculate the branching ratio for B -> J/psi + anything, within the color-singlet approximation for J/psi production, but including perturbative QCD corrections beyond the leading logarithm approximation. Such higher order corrections…
The inclusive spectra of radiative and semi-leptonic B-meson decays near the endpoint is computed taking into account renormalons in the Sudakov exponent (Dressed Gluon Exponentiation). In this framework we demonstrate the factorization of…
In this paper, we summarize the existing methods of solving the evolution equation of the leading-twist $B$-meson LCDA. Then, in the Mellin space, we derive a factorization formula with next-to-leading-logarithmic (NLL) resummation for the…
We discuss applications of the perturbative QCD approach in the exclusive non-leptonic two body B-meson decays. We briefly review its ingredients and some important theoretical issues on the factorization approaches. PQCD results are…
Two-body charmless hadronic B decays involving a tensor meson in the final state are studied within the framework of QCD factorization (QCDF). Due to the G-parity of the tensor meson, both the chiral-even and chiral-odd two-parton…
Analytic formulae are given for order alpha_s perturbative QCD corrections to the double differential distribution of the tau lepton energy and the invariant mass of the tau + antineutrino system in semileptonic decays of the bottom quark.…
We have recently presented the complete O(alpha_s^2) corrections to the semileptonic decay width of the b quark at maximal recoil. Here we discuss various technical aspects of that calculation and further applications of similar methods. In…
Nonfactorizable contributions to exclusive two-body nonleptonic weak decays of heavy mesons arising from color octet currents, characterized by the parameter $r_2$, are extracted from the data. It is found that $r_2$ is equal to $\sim…
In high energy exclusive processes involving leptons, QED corrections can be sensitive to infrared scales like the lepton mass and the soft photon energy cut, resulting in large logarithms that need to be resummed to all order in $\alpha$.…
Building on the recent derivation of a bare factorization theorem for the $b$-quark induced contribution to the $h\to\gamma\gamma$ decay amplitude based on soft-collinear effective theory, we derive the first renormalized factorization…
Two-gluon radiative corrections to the $b\to c\ell\nu$ decay width have been computed analytically as an expansion in terms of \frac{m_c}{m_b} << 1 in the kinematical limit of zero lepton invariant mass. The obtained results match smoothly…
We discuss the QCD corrections to the large-$m_t$ electroweak contributions to $\Delta r$ and to the process $Z\to b \bar b$ as two of the most representative examples. This needs the construction of an effetive field theory below the top…
The production of a pair of on-shell $Z$-bosons is an important process at the Large Hadron Collider. Owing to its large production cross section at the LHC, this process is very useful for SM precision studies, electroweak symmetry…
Applying the dispersion approach we compute perturbative QCD corrections to the power suppressed soft contribution of $B \to \gamma \ell \nu$ at leading twist. QCD factorization for the $B \to \gamma^{\ast}$ form factors is demonstrated…
Compact analytic expressions have been obtained for the first order perturbative QCD corrections to the inclusive spectra of the leptons in the semileptonic decays of polarised heavy quarks. Charmed and beautiful $\Lambda$ baryons from…
We discuss nonfactorizable $1/N_c$ contributions in the amplitudes of non-leptonic exclusive decays of the type $B\rightarrow D\pi$ ($N_c$ is the number of colors). In a certain kinematical limit rather reliable estimates are possible. It…
Non-leptonic two-body decays are discussed on the basis of a generalized factorization approach. It is shown that a satisfactory description of numerous decay processes can be given using the same two parameters a_1^{eff} and a_2^{eff}.…
We consider the longitudinal momentum distribution of hadrons inside jets in proton-proton collisions. At partonic threshold large double logarithmic corrections arise which need to be resummed to all orders. We develop a factorization…
We perform a global analysis of three-body charmless hadronic decays $B\to VP_3\to P_1P_2P_3$ in the perturbative QCD (PQCD) approach, where $V$ denotes an intermediate vector resonance, and $P_i$, $i=1,2,3$, denote final-state pseudoscalar…
In the framework of nonrelativistic QCD, we compute the leading double-logarithmic corrections of order alpha_s^3 ln^2(1/alpha_s) to the heavy-quark-antiquark bound-state wave function at the origin, which determines the production and…