Related papers: J/psi D*D* vertex from QCD sum rules
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…
The iso-vector axial-vector form factors of the \Delta-\Delta transition are calculated in the framework of the Light-cone QCD sum rules method. Also, axial charge of \Delta baryon is predicted.
QCD sum rules on the light-cone are derived for the sum $f^+ + f^-$ of the $B\to \pi$ and $D\to \pi$ form factors taking into account contributions up to twist four. Combining the results with the corresponding $f^+$ form factors calculated…
We study the shape parameters of the $D\pi$ scalar and vector form factors using as input dispersion relations and unitarity for the moments of suitable heavy-light correlators evaluated with Operator Product Expansions, including…
The strong coupling constants are basic quantities that carry information of the strong interactions among the baryon and meson multiplets as well as information on the natures and internal structures of the involved hadrons. These…
In this article, we study the vertices $DDV$ and $D^*DV$ with the light-cone QCD sum rules. The strong coupling constants $g_{DDV}$ and $f_{D^*DV}$ play an important role in understanding the final-state re-scattering effects in the…
The strong coupling constants of the $\pi$ and $K$ mesons with negative parity octet baryons are estimated within the light cone QCD sum rules. It is observed that all strong coupling constants, similar to the case for the positive parity…
We investigate the $\omega\sigma\gamma$-vertex and estimate the coupling constant g$_{\omega\sigma\gamma}$ in the framework of the light cone QCD sum rules. We compare our result with the values of this coupling constant deduced from a…
We use three-point function QCD sum rules to calculate the form factor $A_0(q^2)$ appearing in the matrix element of the flavour-changing axial current between the $D (B)$ state and a vector meson state. We describe the role of this form…
We determine the strong coupling constant $\alpha_s$ from a lattice calculation of vacuum polarization functions (VPF) in three-flavor QCD with dynamical overlap fermions. Fitting lattice data of VPF to the continuum perturbative formula…
The strong coupling constants of heavy baryons with light vector mesons are calculated in the framework of the light cone QCD sum rules using the most general form of the interpolating currents for the heavy baryons. It is shown that the…
We present a sum-rule calculation of the decay constants of the charmed vector mesons $D^*$ and $D^*_s$ from the two-point correlator of vector currents. First, we show that the perturbative expansion in terms of the pole mass exhibits no…
Motivated by the recent work on the calculation of the $\pi NN$ coupling constant using QCD sum rule beyond the chiral limit, we construct the corresponding sum rules for the couplings, $\eta NN$, $\pi \Xi\Xi$, $\eta \Xi\Xi$, $\pi \Sigma…
The coupling constants g$_{\rho\eta\gamma}$ and g$_{\omega\eta\gamma}$ are calculated using QCD sum rules method by studying the three point ${\rho\eta\gamma}$ and ${\omega\eta\gamma}$ correlation functions. A comparison of the results with…
In this work, we studied the Borel masses relation used in QCDSR calculations. These masses are the parameters of the Borel transform used when the three point function is calculated. We analised an usual and a more general linear…
The hadronic tensor molecule $\mathcal{M}=J/\psi J/\psi$ is investigated in the framework of QCD sum rule method. We evaluate its mass and current coupling using the two-point SR approach. Our result $m=(6290 \pm 50)~ \mathrm{MeV}$ for the…
The radiative decays $ B^{*} (D^{*})\to B(D) \gamma$ are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson decays…
In this article, we study the contribution from the final-state interactions to the strong coupling constant $g_{D^* D \pi}$. We take an assumption that the momentum transfers in the strong decay $D^{*+} \to D^0 \pi^+$ be large to validate…
We show that in the context of QCD sum rules a strong (anti-) correlation between the $b$-quark mass $m_b$ and the $B$-meson's decay constant $f_B$ emerges: $\delta f_B/f_B\approx -8 \delta m_b/m_b.$ This observation allows us to derive a…
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…