Related papers: g_phi-pion-gamma coupling constant in light cone Q…

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…

We employ QCD sum rules to calculate the coupling constant g$_{\rho\sigma\gamma}$ by studying the three point ${\rho\sigma\gamma}$-correlation function. Our results is consistent with the value of this coupling constant obtained using…

We point out subtleties in the previous sum rule calculations of the $\pi NN$ coupling associated with using either the PV or the PS coupling schemes in modeling the phenomenological side. We propose a sum rule which is independent of the…

The pion-nucleon coupling constant $g_{\pi N}$ is studied on the basis of the QCD sum rules. Both the Borel sum rules and the finite energy sum rules for $g_{\pi N}$ are used to examine the effects of higher dimensional operators (up to…

We calculate the strong coupling constants g_(P^(**)P^(*)\pi), where P^(**)(D^(**), B^(**)) is the 1^+ p-wave state, in the framework of the light cone QCD sum rules, and using these values of g_(P^(**)P^(*) pi, we compute the hadronic…

The light cone QCD sum rules method is used to calculate the transition form factor for the radiative (phi -> f_0 gamma) decay, assuming that the quark content of the (f_0) meson is pure (bar{s}s) state. The branching ratio is estimated to…

The "g_{Delta N gamma}" coupling for the "Delta -> N gamma" decay is calculated in framework of the light cone QCD sum rules and is found to be g_{Delta N gamma} = (1.6 pm 0.2) GeV^(-1). Using this value of g_{Delta N gamma} we estimate the…

We evaluate the $\pi N$ coupling constant using a QCD sum rule based on the pion-to-vacuum matrix element of the correlator of two interpolating nucleon fields. The part of the correlator with Dirac structure $k\llap/\gamma_5$ is used,…

The light cone QCD sum rules are derived for the $\pi NN$ coupling $g_{\pi NN}$ and $\pi NN(1535)$ coupling $g_{\pi NN^\ast}$. The contribution from the excited states and continuum is subtracted cleanly through double Borel transformation.…

We evaluate the pi-N-N, pi-Sigma-Sigma and pi-Sigma-Lambda coupling constants using QCD sum rules based on pion-to-vacuum matrix elements of correlators of two interpolating baryon fields. The parts of the correlators with Dirac structure…

The strong coupling constants g_{K LAMBDA N} and g_{K SIGMA N} for the structure (sigma_{mu,nu} gamma_5) are calculated within light cone QCD sum rules. A comparison of our results on these couplings with predictions from traditional QCD…

The coupling constants g_{\pi \Lambda \Sigma} and g_{K \Sigma \Xi} are calculated in the QCD sum rule approach using the three-point function method and taking into account the SU(3) symmetry breaking effects. The pattern of SU(3) breaking…

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…

The coupling constant of a0-->rho-gamma and f0-->rho-gamma decays are calculated using 3-point sum rule. We estimate the coupling constant g_a0-rho-gamma and g_f0-rho-gamma which are an essential ingredient in the analysis of physical…

We calculate the coupling constants, $g_{\pi NS_{11}}$ and $g_{\eta NS_{11}}, using QCD sum rules in the presence of an external meson field. A covariant derivative is introduced within the S_{11} interpolating field so that in the…

The QCD sum rule calculation of the in-medium pion decay constants using pseudoscalar-axial vector correlation function, $i \int d^4x e^{ip\cdot x} < \rho| T[{\bar d}(x) i \gamma_5 u (x) {\bar u}(0) \gamma_\mu \gamma_5 d (0)] | \rho>$ is…

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…

The light cone QCD sum rules are derived for the $K^\ast K\pi$ coupling $g_{K^\ast K\pi} $ and the $\rho\pi\pi$ coupling $g_{\rho\pi\pi}$. The contribution from the excited states and the continuum is subtracted cleanly through the double…

We calculate the form factors V, A_1, A_2 and A_0 appearing in the (D -> phi) transition in light cone QCD sum rule method. We compare our results on these form factors with the current experimental results and existing theoretical…

The couplings of pions with heavy baryons g_2 (\Sigma^*, \Sigma) and g_3(\Sigma^*, \Lambda) are studied with light-cone QCD sum rules in the leading order of heavy quark effective theory. Both sum rules are stable. Our results are…