相关论文: K-meson vector and tensor decay constants and BK-p…
We present a detailed analysis of the Bc form factors in the BSW framework, by investigating the effects of the flavor dependence on the average transverse quark momentum inside a meson. Branching ratios of two body decays of Bc meson to…
Recent results for B meson decay constants with NRQCD b-quarks and clover light quarks are discussed. Perturbative matching factors through O($\alpha/M$) are now available and incorporated into the analyses. An O($\alpha a$) improvement…
The properties of the B-meson light-cone wave function up to next-to-leading order Fock state expansion have been studied through a comparative study of the $B\to \pi$, $K$ transition form factors within the $k_T$ factorization approach and…
We present a study of leptonic $B$ meson decay constants in lattice QCD with two flavors ($N_f=2$) of light dynamical quarks using NRQCD for the heavy quark. Gauge configurations are generated with a renormalization-group improved gauge…
We present a lattice QCD determination of the b quark mass and of the B and B_s decay constants, performed with N_f=2 twisted mass Wilson fermions, by simulating at four values of the lattice spacing. In order to study the b quark on the…
Preliminary results on spectrum and decay constant of $B$ mesons from a quenched simulation at $\beta = 6.0$ on an $16^3\times48$ lattice are discussed. The heavy quark has been implemented using both an NRQCD and the static formulation,…
In quark models \`a la Bakamjian and Thomas, that yield covariance and Isgur-Wise scaling of form factors in the heavy quark limit, we compute the decay constants $f^{(n)}$ and $f^{(n)}_{1/2}$ of S-wave and P-wave mesons composed of heavy…
The form factors parameterizing the B_c semileptonic matrix elements can be related to a few invariant functions if the decoupling of the spin of the heavy quarks in B_c and in the mesons produced in the semileptonic decays is exploited. We…
A brief review of the current state of observed deviations of theoretical predictions from experimental data in semileptonic decays of $B$ and $B_c$ mesons is given. A theoretical analysis of these decays is carried out, taking into account…
We study Cabibbo-Kobayashi-Maskawa (CKM) favored weak decays of Bc mesons in the Isgur-Scora-Grinstein-Wise (ISGW) quark model. We present a detailed analysis of the Bc meson decaying to a pseudoscalar meson (P) and an axial-vector meson…
We present a lattice QCD determination of the vector and scalar form factors of the kaon semileptonic decay $K \to \pi \ell \nu$, which is relevant for the determination of the CKM matrix element $|V_{us}|$ from experimental data. Our…
We apply the perturbative QCD factorization theorem developed recently for nonleptonic heavy meson decays to the radiative decay $B\to K^*\gamma$. In this formalism the evolution of the Wilson coefficients from the $W$ boson mass down to…
We present a determination of the ratio of kaon and pion leptonic decay constants in isosymmetric QCD (isoQCD), $f_K / f_\pi$, making use of the gauge ensembles produced by the Extended Twisted Mass Collaboration (ETMC) with $N_f = 2 + 1 +…
We present calculations of the decay constants and kaon B-parameter $B_K$ as the first stage of RBC Collaboration's quenched numerical simulations using DBW2 gauge action and domain-wall fermions. Some of potential systematic errors and…
We present a sum-rule extraction of the decay constants of the D, Ds, B, and Bs mesons from the two-point correlator of heavy-light pseudoscalar currents [1]. Our main emphasis is laid on the control over the uncertainties in the decay…
We present results for the matrix elements of the additional $\Delta S=2$ operators that appear in models of physics beyond the Standard Model (BSM), expressed in terms of four BSM $B$-parameters. Combined with experimental results for…
The form factors for the semileptonic decays of heavy-light pseudoscalar mesons of the type $D \to Ke\nu$ are studied in quenched lattice QCD at $\beta=6.0$ using Wilson fermions. We explore new numerical techniques for improving the signal…
We study the exclusive semileptonic $B$-meson decays $B\to K(\pi)\ell^+\ell^-$, $B\to K(\pi)\nu\bar\nu$, and $B\to\pi\tau\nu$, computing observables in the Standard model using the recent lattice-QCD results for the underlying form factors…
We calculate the $B_{u,d,s}\to T$ form factors within the framework of the perturbative QCD approach, where $T$ denotes a light tensor meson with $J^P=2^+$. Due to the similarities between the wave functions of a vector and a tensor meson,…
We review various B meson decays that require knowledge of the transverse decay constant of the b1(1235) meson. We report on an exploratory lattice QCD calculation of the transverse decay constant of the b1 meson. The lattice QCD…