Related papers: Decay ${\mathit{D} \to} {{\mathit K}^{(*)}}{{\math…
The form factors for the $K_{\ell 3}$ semileptonic decay are computed to order $O(p^4)$ in generalized chiral perturbation theory. The main difference with the standard $O(p^4)$ expressions consists in contributions quadratic in quark…
We investigate the exclusive semileptonic and rare $D\to \pi(K)$ decays within the standard model together with the light-front quark model (LFQM) constrained by the variational principle for the QCD-motivated effective Hamiltonian. The…
The branching fractions of the semileptonic and rare $B_s$ decays are calculated in the framework of the QCD-motivated relativistic quark model. The form factors of the weak $B_s$ transitions are expressed through the overlap integrals of…
The form factors of weak decays of $B_s$ mesons to ground state $D_s^{(*)}$ mesons as well as to their radial $D_s^{(*)}(2S)$ and orbital $D_{sJ}^{(*)}$ excitations are calculated in the framework of the relativistic quark model based on…
Coupled-channel effects are taken into account for the study of scalar form factors in semi-leptonic $D\to\pi\bar{\ell}\nu_\ell$ and $D\to \bar{K}\bar{\ell}\nu_\ell$ decays, by solving the Muskhelishvili-Omn\`es integral equations. As…
We present a lattice-QCD determination of the $\Lambda \to p$ vector and axial-vector form factors, providing theoretical input for studies of the semileptonic decay $\Lambda \to p\ell\bar{\nu}_\ell$. The calculation is carried out on a…
Experimental checks of the second row unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix involve extractions of the matrix element $V_{cd}$, which may be obtained from semileptonic decay rates of $D$ to $\pi$. These decay rates are…
We study the radiative and weak nonleptonic decays of vector B-mesons within the covariant confined quark model (CCQM) developed in our previous papers. First, we calculate the matrix elements and decays widths of the radiative decays…
Using the light-front quark model, we calculate the transition form factors, decay rates, and longitudinal lepton polarization asymmetries for the exclusive rare $B\to K\ell^+\ell^-(\ell=e,\mu,\tau$) decays within the standard model.…
Semi-leptonic $B$ decays provide promising channels to test the Standard Model, search for signs of new physics, or determine fundamental parameters like CKM matrix elements. We present an update on our calculation of short distance…
We present a calculation of the form factors, $f_0$ and $f_+$, for the $B_{(s)} \to D_{(s)}$ semileptonic decays. Our work uses the MILC $n_f=2+1$ AsqTad configurations with NRQCD and HISQ valence quarks at four values of the momentum…
By globally analyzing all existing measured branching fractions and partial rates in different four momentum transfer-squared $q^2$ bins of $D\to Ke^+\nu_e$ decays, we obtain the product of the form factor and magnitude of CKM matrix…
We present updates for our nonperturbative lattice QCD calculations to determine semileptonic form factors for exclusive $B\to \pi\ell\nu$, $B\to D \ell\nu$, $B_s\to K\ell \nu$, and $B_s\to D_s\ell\nu$ decays. Our calculation is based on…
We present a lattice QCD determination of the vector and scalar form factors of the semileptonic decays D->\pi l \nu and D -> K l \nu which are relevant for the extraction of the CKM matrix elements |Vcd| and |Vcs| from experimental data.…
We investigate the exclusive semilpetonic decays of $\Lambda^{+}_{c}\to (\Lambda/n) \ell^{+} \nu_{\ell}~(\ell=e,\mu)$ within the standard model by using the light-front quark model (LFQM). The form factor behaviors are obtained from the…
We reanalyze the decay constants of s-wave and p-wave mesons and D, B ->M form factors, where M represents a pseudoscalar meson, a vector meson, a scalar meson, or an axial vector meson within a covariant light-front quark model. The…
We study $B_c \to (D,\,D^{\ast})\,l\,\nu$ semileptonic decays mediated via $b \to u\,l\,\nu$ charged current interactions using the $B_c \to (D,\,D^{\ast})$ transition form factors obtained in the covariant light front quark model. We give…
We calculate $D_s^+\to \phi$ transition form factors $V$, $A_0$, $A_1$ and $A_2$, and study semileptonic decay of $D_s^+\to \phi \bar{\ell}\nu$ based on QCD sum rule method. We compare our results of the ratios of $V(0)/A_1(0)$,…
In this paper we investigate weak decays of heavy mesons in the framework of a covariant quark model, which is based on the Bethe-Salpeter equation in instantaneous approximation. Apart from a phenomenological confinement potential, a…
Within the frameworks of the light-front quark model (LFQM) and chiral perturbation theory (ChPT) of $O(p^6)$, we reevaluate the form factors of the $K^+ \to \gamma$ transition. We use these form factors to study the decay of $K^+ \to e^+…