相关论文: Factorization and Decay Constants $f_{D_s^*}$ and …

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…

We have studied the decay $\bar{B} \to D\ell\bar{\nu}$, where $\ell=e or \mu$. From a fit to the differential decay rate $d\Gamma/dw$ we measure the rate normalization ${\cal F}_D(1)|V_{cb}|$ and form factor slope $\hat{\rho}^2_D$, and,…

After improving the knowledge about residua of the semileptonic form factor at its first two poles we show that $f_+^{D\pi}(q^2)$ is not saturated when compared with the experimental data. To fill the difference we approximate the rest of…

The leptonic decay of $D^+$-meson has attracted significant interest due to its unique characteristics. In this paper, we carry out an investigation into the $D^+$-meson leptonic decays $D^+\to \ell^+\nu_{\ell}$ with $\ell=(e,\mu,\tau)$ by…

Using 226 million $B\bar{B}$ events recorded on the $\Upsilon(4S)$ resonance with the BABAR detector at the SLAC $e^+e^-$ storage rings PEPII, we reconstruct $B^-\to D^{*0} e^-\bar\nu_e$ decays using the decay chain $D^{*0}\to{}D^0{}\pi^0$…

We determine the rate for $D_s^* \rightarrow D_s \gamma$ for the first time from lattice QCD and include the full effect of $u$, $d$ and $s$ sea quarks. The valence quarks are implemented using the Highly Improved Staggered Quark (HISQ)…

The longitudinal polarization fraction of the $D^{*}$ meson is measured in $B^0\to D^{*-}\tau^{+}\nu_{\tau}$ decays, where the $\tau$ lepton decays to three charged pions and a neutrino, using proton-proton collision data collected by the…

In the framework of heavy quark effective theory, the leading order Isgur-Wise form factors relevant to semileptonic decays of the ground state $\bar{b}s$ meson $B_{s}$ into orbitally excited $D$-wave $\bar{c}s$ mesons, including the newly…

Using three point QCD sum rules method, the form factors relevant to the semileptonic $B_{s}\to D_{sJ}(2460)\ell\nu$ decay are calculated. The $q^2$ dependencies of these form factors are evaluated. The dependence of the asymmetry parameter…

The form factors and coupling constants of the meson vertices J/\psi D_s D_s and \phi D_s D_s were calculated using three point correlation functions within the QCD Sum Rules formalism. We have considered the cases where \phi, D_s and…

We present a lattice quantum chromodynamics determination of the ratio of the scalar and vector form factors for two semileptonic decays of the $B_s$ meson: $B_s \rightarrow K \ell \nu$ and $B_s \rightarrow D_s \ell \nu$. In conjunction…

Based on $10.64~\mathrm{fb}^{-1}$ of $e^+e^-$ collision data taken at center-of-mass energies between 4.237 and 4.699 GeV with the BESIII detector, we study the leptonic $D^+_s$ decays using the $e^+e^-\to D^{*+}_{s} D^{*-}_{s}$ process.…

We compute the decay constants for the heavy--light pseudoscalar mesons in the quenched approximation and continuum limit of lattice QCD. Within the Schrodinger Functional framework, we make use of the step scaling method, which has been…

A relativistic constituent quark model is adopted to give an unified description of the leptonic and semileptonic decays of pseudoscalar mesons (\pi, K, D, D_s, B, B_s). The calculated leptonic decay constants and form factors are found to…

We present an update of the D meson decay constant f_D using the Highly Improved Staggered Quark (HISQ) action for valence charm and light quarks on MILC N_f = 2+1 lattices. The new determination incorporates HPQCD's improved scale r_1^{N_f…

We compute the Standard Model semileptonic vector and axial-vector form factors for $B_s\to D_s^*$ decay across the full $q^2$ range using lattice QCD. We use the Highly Improved Staggered Quark (HISQ) action for all valence quarks,…

We present an update of our calculations of the decay constants of the D, D_s, B, and B_s mesons in unquenched 2+1 flavor QCD. We use the MILC library of improved staggered gauge ensembles at lattice spacings 0.09, 0.12, and 0.15 fm, clover…

We present a unified analysis of $\overline{B}^0 \to D^{(*)+}\ell^-\bar{\nu}_\ell$ and $\overline{B}^0 \to D^{(*)+}\pi^-$ decays using the perturbative QCD (PQCD) approach. The $B \to D^{(*)}$ transition form factors are calculated at low…

Using 2.92 fb$^{-1}$ of electron-positron annihilation data collected at a center-of-mass energy of $\sqrt{s}= 3.773$ GeV with the BESIII detector, we present an improved measurement of the branching fraction $\mathcal{B}(D^+ \to \omega e^+…

The CLEO Collaboration recently reported the observation of the $B^0\to D^{*-}p\bar{n}$ mode at a rate only a factor of 4--5 lower than $B^0\to D^{*-}\rho^+$ and $D^{*-}\pi^+$. We try to understand this with a factorization approach of…