Related papers: $B^{\ast}_{s1}B^{\ast}K$ form factor from QCD sum …
The coupling constant of f0-->omega-gamma decay is calculated using 3-point sum rule and light cone QCD sum rules. We investigate the results within the two-models which depend on mixing angle.
We discuss the extraction of form factors from three-point sum rules making use of harmonic-oscillator model, where we derive the exact expression for the relevant correlator. We determine the form factor of the ground state by the standard…
We calculate $\bar{B}_s^0\to \phi$ translation form factors $V$, $A_0$, $A_1$, $A_2$ based on QCD sum rule and study the nonleptonic two-body decay of $\bar{B}_s^0\to J/\psi \phi$ with the form factors obtained. We calculate the…
We present results for the $B \rightarrow \pi$ and $D\rightarrow \pi$ form factors derived from QCD sum rules on the light-cone. Our predictions are compared with experiment and used to extract the quark mixing parameter $|V_{ub}|$ from a…
In this article, the three point QCD sum rules is used to compute the strong coupling constants of vertices containing the strange bottomed ( charmed ) mesons with pion. The coupling constants are calculated, when both the bottom ( charm )…
The form factors of the semileptonic $B_c\to S(AV)\ell\nu$ $(\ell=\tau, \mu, e)$ transitions, where S and AV denote the scalar $X_{c0}$ and axial vector $(X_{c1}, h_{c})$ mesons, are calculated within the framework of the three-point QCD…
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…
We analyse B_{d,s} -> K(*)0 K(*)0 modes within the SM, relating them in a controlled way through SU(3)-flavour symmetry and QCD-improved factorisation. We propose a set of sum rules for such penguin-mediated decays to constrain some CKM…
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 derive new QCD sum rules for the axial coupling constants by considering two-point correlation functions of the axial-vector currents in a one nucleon state. The QCD sum rules tell us that the axial coupling constants are expressed by…
The external-field QCD Sum Rules method is used to evaluate the coupling constant of the light isoscalar-scalar meson (``$\sigma$'' or \epsilon) to the nucleon. The contributions that come from the excited nucleon states and the response of…
We present preliminary results on the longitudinal $and$ transverse form factors of the quark-gluon vertex as functions of the incoming and outgoing quark momenta and an angle $\theta =2\pi/3$ between them. The expressions for these form…
We derive new QCD sum rules for $B\to D$ and $B\to D^*$ form factors. The underlying correlation functions are expanded near the light-cone in terms of $B$-meson distribution amplitudes defined in HQET, whereas the $c$-quark mass is kept…
A comprehensive study of $b\to c$ weak decays of doubly heavy baryons is presented in this paper. The transition form factors as well as the pole residues of the initial and final states are respectively obtained by investigating the…
QCD sum rules are used to calculate the $q^2$ dependence of the $\pi NN$ coupling $g_{\pi NN} (q^2)$ in the spacelike region $0.5 \ {\mbox{GeV}}^2 \lesssim q^2 \lesssim 1.5\ {\mbox{GeV}}^2$. We study the Borel sum rule for the three point…
We study the strong interactions among the heavy bottom spin--1/2 $\Sigma_b$ baryon, nucleon and $B$ meson as well as the heavy charmed spin--1/2 $\Sigma_c$ baryon, nucleon and $D$ meson in the context of QCD sum rules. We calculate the…
We discuss the extraction of ground-state parameters, such as decay constants and form factors, from two- and three-point dispersive sum rules, making use of a quantum-mechanical potential model. This model provides a unique possibility to…
We reanalyze the $B\to M$ tensor form factors in a covariant light-front quark model, where $M$ represents a vector meson $V$, an axial-vector meson $A$, or a tensor meson $T$. The treatment of masses and mixing angles in the $K_{1A,1B}$…
The external-field QCD Sum Rules method is used to evaluate the coupling constants of the light-isoscalar scalar meson (``\sigma'' or \epsilon) to the \Lambda, \Sigma, and \Xi baryons. It is shown that these coupling constants as calculated…
In this article, we study momentum dependence of the hadronic coupling constants $G_{B_c^* B_c \Upsilon}$, $G_{B_c^* B_c J/\psi}$, $G_{B_c B_c \Upsilon}$ and $G_{B_c B_c J/\psi}$ with the off-shell $\Upsilon$ and $J/\psi$ using the…