相关论文: Parametrisations of the D -> K l nu form factor an…

Using the standard parametrization of the dipole form, we have studied the vulnerability of $Q^2$ on the vector form factors ($f_i^{B_iB_f}(Q^2)$) and axial-vector form factors ($g_i^{B_iB_f}(Q^2)$), $i=1,2,3$ computed for the semileptonic…

We calculate the form factors for the semileptonic decays of the $B$ meson to $D$ and $D^*$ mesons in a Bethe-Salpeter model. We show that our model is consistent with the constraints of Heavy Quark Effective Theory (HQET) and we extract…

We point out that current experimental data for partial B --> pi l nu branching fractions reduce the theoretical input required for a precise extraction of |V_ub| to the form factor normalization at a single value of the pion energy. We…

We analyse the semileptonic decay D+ -> K- pi+ l+ nu(l) using an effective Lagrangian developed previously to describe the decays D -> P l nu(l) and D -> V l nu(l). Light vector mesons are included in the model which combines the heavy…

We update the determination of |V_us| using semielectronic and semimuonic decays of K mesons. A modest improvement of 15% with respect to its present value is obtained for the error bar of this matrix element when we combine the four…

Motivated by more precise recent measurements of the $B \to \eta \ell \nu$ and $D_{(s)} \to \eta^{(\prime)}\ell \nu$ decays, we employ state-of-the-art parametrizations to describe the $B_{(s)}, D_{(s)} \to \eta^{(\prime)}$ form factors…

A symmetry-preserving continuum approach to meson bound-states in quantum field theory, employed elsewhere to describe numerous $\pi$- and $K$-meson electroweak processes, is used to analyse leptonic and semileptonic decays of $D_{(s)}$…

We compute semi-leptonic $B_s$ decay form factors using Heavy Quark Effective Theory on the lattice. To obtain good control of the $1/m_b$ expansion, one has to take into account not only the leading static order but also the terms arising…

Heavy-to-heavy semileptonic decays, particularly the bottom-to-charm quark transitions, are essential for testing the Standard Model (SM) and extracting the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements. These decays have been extensively…

We investigate the form factors for exclusive semileptonic decays of $B$-meson to $D,~D^*$, based on the parton picture and helped by the results of the HQET. We obtain the numerical results for the slope of the Isgur-Wise function, which…

We analyze charm meson semileptonic decays using the measured ratios $\Gamma_L/\Gamma_T$ and $\Gamma_{+}/\Gamma_{-}$ from $D\to {\bar K}^{*}$ and the branching ratios for $D \to {\bar K}^{*}$ and $D \to {\bar K}$. First we introduce the…

We present a lattice determination of the vector and scalar form factors of the $D\to\pi(K)\ell\nu$ semileptonic decays, which are relevant for the extraction of the CKM matrix elements $|V_{cd}|$ and $|V_{cs}|$ from experimental data. Our…

The semileptonic decay of heavy flavor mesons offers a clean environment for extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements, which describes the CP-violating and flavor changing process in the Standard Model. The involved…

We examine the rates for the exclusive decays $B\to K^{(*)}\ell^+\ell^-$. We use the scaling predictions of the heavy quark effective theory to extract the necessary form factors from fits to various combinations of data. These data include…

$B_s^0\rightarrow D_s^{-}$ and $B_s^0\rightarrow D_s^{*-}$ weak transition form factors are estimated for the whole physical region with a method based on an instantaneous approximated Mandelstam formulation of transition matrix elements…

We present lattice results for the form factors relevant in the K -> pion and D -> pion semileptonic decays, obtained from simulations with two flavors of dynamical twisted-mass fermions and pion masses as light as 260 MeV. For K -> pion…

The form factors relevant to $B_{q}\to D^{\ast}_{q}(J^{P}=1^{-}) ell\nu$ $(q=s, d, u)$ decays are calculated in the framework of the three point QCD sum rules approach. The heavy quark effective theory prediction of the form factors as well…

We present a unified method for analysing form factors in B -> pi l nu-bar_l and B -> K* gamma decays. The analysis provides consistency checks on the q^2 and 1/M extrapolations necessary to obtain the physical decay rates. For the first…

We present precision corrections to dispersion relation bounds on form factors in bottom hadron semileptonic decays and analyze their effects on parameterizations derived from these bounds. We incorporate QCD two-loop and nonperturbative…

We study in detail the prediction for the semileptonic decays $\bar{B} \to D (D^*) \pi \ell \bar{\nu}$ by heavy quark and chiral symmetry. The branching ratio for $\bar{B} \to D \pi \ell \bar{\nu}$ is quite significant, as big as…