相关论文: Three-Scale Factorization Theorem and Effective Fi…
Using the renormalon calculus, we study the asymptotic behavior of the perturbative expansion of the hard-scattering kernels entering the QCD factorization formula for the nonleptonic weak decays B->D M, where M is a light meson. In the…
We give a selection of results on spectrum and decay constants of light and heavy-light hadrons. Effective field theories relevant for their lattice calculation, namely non-relativistic QCD (NRQCD) for heavy quarks on the lattice and Chiral…
Predicting phenomena that mix few-photon quantum optics with strong field nonlinear optics is hindered by the use of separate theoretical formalisms for each regime. We close this gap with a unified effective field theory valid for…
We construct a factorization theorem that allows to systematically include QCD corrections to the contribution of the electromagnetic dipole operator in the effective weak Hamiltonian to the $\bar B_s \to \mu^+\mu^-$ decay amplitude. We…
The soft-collinear effective theory has been recently applied to prove novel factorization theorems for many B decays. We describe here in some detail the factorization relation for color-supressed nonleptonic B -> D(*)0 pi0 decays and…
Two-body weak decays of bottom mesons into two pseudoscalar mesons are examined employing SU(3) flavor symmetry for the nonfactorizable matrix elements. Using certain measured Cabibo-favored modes, we fix the reduced matrix elements and…
We calculate the form factors for weak decays of $B_{(s)}$ and $D_{(s)}$ mesons to light pseudoscalar and vector mesons. To reveal the intimate connection between different decay modes and to be able to perform the calculations in the full…
We discuss a model-independent framework for the analysis of the radiative B-meson decays B -> K* gamma and B -> rho gamma based on the heavy-quark limit of QCD. We present a factorization formula for the treatment of B -> V gamma matrix…
We construct model-independent parametrizations of the individual QCD form factors relevant to Lambda_b --> Lambda_c l nu decays. These results follow from dispersion relations and analyticity, and incorporate an improvement in the…
Since an old observation by Beenakker et al, the evaluation of QCD processes in dimensional reduction has repeatedly led to terms that seem to violate the QCD factorization theorem. We reconsider the example of the process gg->ttbar and…
We argue that consistency of the combined heavy quark and chiral effective lagrangian requires the QCD scale which multiplies $1/M$ in the heavy quark expansion to be the chiral symmetry breaking scale, $\Lambda_{CSB}$, rather than the QCD…
The accurate calculation of weak heavy-to-light form factors is crucial for the determination of CKM matrix elements from experimental data on B decays. In SCET, the soft-collinear effective theory, these form factors can, in the heavy…
We present an all-order generalized factorization formula for QCD scattering amplitudes in kinematical configurations where two or more momenta of the external partons become collinear. The singular behaviour of the scattering amplitudes in…
We consider rare semileptonic decays of a heavy $D$-meson into a light vector meson in the framework of QCD factorization. In contrast to the corresponding $B$-meson decays, the naive factorization hypothesis does not even serve as a first…
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…
We analyze quasi-two-body charmless $B$ decays $B_{(s)} \to P_1 V \to P_1 P_2 P_3$ with $V$ representing a vector resonant, and $P_{1,2,3}$ as a light pseudo-scalar meson, pion, kaon or $\eta^{(\prime)}$. The intermediate processes $B_{(s)}…
We analyze the charmless two-body decays of the $B$ meson into a pseudoscalar and a vector meson, referred to as $B\to PV$ decay, within the framework of the modified perturbative QCD (PQCD) approach. Based on the conventional PQCD…
Since b quark mass is not asymptotically large, chirally enhanced corrections which arise from twist-3 wave functions may be important in B decays. We thus evaluate the hadronic matrix elements with the emitted meson described by leading…
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…
Previous work has shown that mesonic fields in chiral Lagrangians can be systematically connected to quark-level operators in QCD sum rules through chiral-symmetry constrained and energy-independent scale factor matrices. This framework…