Related papers: Factorization and Decay Constants $f_{D_s^*}$ and …
Based on the predictions of the relevant form factors from the covariant light-front quark model, we show the branching fractions for the $D (D_s) \to (P,\,S,\,V,\,A)\,\ell\nu_\ell$ ($\ell=e$ or $\mu$) decays, where $P$ denotes the…
I report preliminary CLEO-c results on purely leptonic decays of the Ds using 195/pb of data at 4.170 GeV. We measure fDs = 280.1 +/- 11.6 +/- 6.0 MeV, and fDs/fD+ = 1.26 +/- 0.11 +/- 0.03.
Analyzing $e^+e^-$ collision data corresponding to an integrated luminosity of $7.33~\mathrm{fb}^{-1}$ collected at center-of-mass energies between 4.128 and 4.226~GeV with the BESIII detector, we measure the branching fraction of the…
We compute the leptonic decay constants $f_{D^+}$, $f_{D_s}$, and $f_{K^+}$, and the quark-mass ratios $m_c/m_s$ and $m_s/m_l$ in unquenched lattice QCD. We use the MILC highly improved staggered quark (HISQ) ensembles with four dynamical…
We study the radiative leptonic $D$ meson decays of $D^+_{(s)}\to \l^+\nu_{\l}\gamma$ ($\l=e,\mu,\tau$), $D^0\to \nu\bar{\nu}\gamma$ and $D^0\to \l^+\l^-\gamma$ ($l=e,\mu$) within the light front quark model. In the standard model, we find…
Using CLEO data collected at 3370 MeV and 4170 MeV, we determine fD = (205.8 +- 8.5 +- 2.5) MeV and an interim preliminary value of fDs = (267.9 +- 8.2 +- 3.9) MeV, where both results are radiatively corrected. They agree with the recent…
We consider the possibility of measuring both $\sin (2 \beta)$ and $\cos (2 \beta)$ in the KM unitarity triangle using the process $B^0 \to D^{*+}D^{*-}K_s$. This decay mode has a higher branching fraction (O(1%)) than the mode $B^0 \to…
Recent measurements of branching fractions, form factors and decay constants of leptonic and semileptonic decays of D_(s)-mesons acquired at experiments running at the Upsilon(4S) resonance energy are reviewed.
We compute decay constants of heavy-light mesons in quenched lattice QCD with a lattice spacing of a ~ 0.04 fm using non-perturbatively O(a) improved Wilson fermions and O(a) improved currents. We obtain f_{D_s} = 220(6)(5)(11) MeV, f_D =…
Using a large sample of D0 to K mu nu and pi mu nu decays collected by the FOCUS photoproduction experiment at Fermilab, we present new measurements of the q^2 dependence for the f+(q^2) form factor. These measured f+(q^2) form factors are…
We present a preliminary measurement of the q2 dependence of the D0 --> K- e+ nu_e decay rate. This rate is proportional to the hadronic form factor squared, specified by a single parameter. This is either the mass in the simple pole ansatz…
We have studied the leptonic decay D^+_s to tau^+ nu_tau, via the decay channel tau^+ to e^+ nu_e anti-nu_tau, using a sample of tagged D_s^+ decays collected near the D^*_s D_s peak production energy in e^+ e^- collisions with the CLEO-c…
In this paper the decay of $B^+_c$ meson, consisting of two b and c heavy quarks, into the $D^0$ and $K^+$ mesons is studied. Given that the experimental branching ratio for this decay is within the range of $3.72\times 10^{-5}$ to…
Assuming the ${\bar D}^0, D^-, D^-_s$ and $B^+, B^0, B_s^0$ mesons belong to triplets of SU(3) flavor symmetry, we analyse the form factors in the semileptonic decays of these mesons. Both quark and meson mass differences are taken into…
The form factors parameterizing the weak $D$ and $D_s$ transitions to light pseudoscalar and vector mesons are calculated in the framework of the relativistic quark model based on the quasipotential approach. The special attention is paid…
We study the decay constants and form factors of the ground-state s-wave and low-lying p-wave mesons within a covariant light-front approach. Numerical results of the B to D** transition form factors, where D** denotes generically a p-wave…
We present a new determination of the Ds decay constant, f_{Ds} using 5 million continuum charm events obtained with the CLEO II detector. Our value is derived from our new measured ratio of widths for Ds -> mu nu/Ds -> phi pi of 0.173+/-…
We examine e+e- to Ds- Ds*+ or Ds-* Ds+ collisions at 4170 MeV using the CLEO-c detector in order to measure the decay constant f_Ds+. We use the Ds+ to ell+ nu channel, where the ell+ designates either a mu+ or a tau+. Analyzing both modes…
We calculate the branching ratio of the non-resonant $B \to D^- \pi^+\pi^+\pi^- $ decay using a simple model based on the framework of the factorization approach. In naive factorization approach, there are only tow tree diagrams for this…
We present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ and of the parameters $\rho^2$, $R_1$, and $R_2$, which fully characterize the form factors of the $B^0 \to D^{*-}\ell^{+}\nu_\ell$ decay in the…