Related papers: The $J/\psi DD^*$ vertex
We present the first calculation on the $\Delta$ axial-vector and pseudoscalar form factors using lattice QCD. Two Goldberger-Treiman relations are derived and examined. A combined chiral fit is performed to the nucleon axial charge, N to…
We compute the strong coupling constant $g_{P^* P \pi}$, with $P$ and $P^*$ respectively pseudoscalar and vector heavy mesons by using the QCD sum rules approach. Our computation is based on the evaluation of the time ordered product of…
We determine matrix elements for $B \to D$ semileptonic decay. The use of the constrained fitting method and multiple smearings for both two- and three-point correlators allows an improved calculation of the form factors.
A momentum dependent quark mass may be incorporated into a quark model in a manner consistent with dynamically broken chiral symmetry. We use this to study the high $Q^2$ behavior of the vector, axialvector, scalar and pseudoscalar…
We derive new sum rules for the form factors of the $B_c\to J/\psi\, \ell \bar{\nu}_\ell$ semileptonic transitions, employing the vacuum-to-$B_c$ correlation function of the $J/\psi$-interpolating and $b\to c$ weak currents. In the heavy…
The electromagnetic and gravitational form factors of $\Omega^-$, a spin-3/2 hyperon composed of three $s$ quarks, are calculated by using a covariant quark-diquark approach. The model parameters are determined by fitting to the form…
Using three point QCD sum rules method, the form factors relevant to the semileptonic Bs ->DsJ (2460)l nu decay are calculated. The q2 dependence of these form factors is evaluated and compared with the heavy quark effective theory…
We calculate the form factors for the heavy-to-light transitions $B\rightarrow \pi,K $ by means of QCD sum rules using $\pi$ and $K$ light-cone wave functions. Higher twist contributions as well as gluonic corrections are taken into…
We calculate the form factors for weak decays of $B_{(s)}$ and $D_{(s)}$ mesons to light pseudoscalar and vector mesons. To reveal the intimate connection between different decay modes and to be able to perform the calculations in the full…
We study the electromagnetic on-shell form factor of quarks in massless perturbative QCD. We derive the complete pole part in dimensional regularization at three loops, and extend the resummation of the form factor to the…
The strong coupling constants, $g_{D_{s}DK_0^*}$, $g_{B_{s}BK_0^*}$, $g_{D^{\ast}_{s}D K}$, $g_{B^{\ast}_{s}BK}$, $g_{D^{\ast}_{s}D K_1}$ and $g_{B^{\ast}_{s}BK_1}$, where $K_0^*$, $K$ and $K_1$ are scalar, pseudoscalar and axial vector…
An explicit model is presented which gives the momentum transfer-dependent ratios of form factors of hadronic currents. For the unknown Isgur-Wise function and its generalization for transitions to light particles a simple phenomenological…
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…
We compute the couplings $DD^*\pi$,$D_1D^*\pi$,$D^*D^*\pi$, $D_1 D_1\pi$ using QCD sum rules. These couplings are important inputs in the meson exchange model calculations used to estimate the amount of $J/\psi$ absorption due to pions and…
We calculate the electromagnetic pion form factor at intermediate space-like momentum transfer from the QCD sum rule for the correlation function of two {\it pseudoscalar } interpolating fields and the electromagnetic current. This…
The $J/\psi \pi\to \bar{D} D^*, \bar{D} D$, ${\bar D}^* D^*$ and ${\bar D} D^*$ cross sections as a function of $\sqrt{s}$ are evaluated in a QCD sum rule calculation. We study the Borel sum rule for the four point function involving…
A method of deriving bounds on the weak meson form factors, based on perturbative QCD, analyticity and unitarity, is generalized in order to fully exploit heavy quark spin symmetry in the ground state $(L=0)$ doublet of pseudoscalar $(B)$…
We use QCD light-cone sum rules with holographic anti de Sitter/Chromodynamics (AdS/QCD) Distribution Amplitudes (DAs) for the $K^*$ meson in order to predict the full set of seven $B \to K^*$ transition form factors for…
We compute the vector meson decay constants fD*, fDs* from the simulation of twisted mass QCD on the lattice with Nf = 2 dynamical quarks. When combining their values with the pseudoscalar D(s)-meson decay constants, we were able (i) to…
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.