Related papers: Coupling Constant for $\mathbf{N^*(1535)N\rho}$
We report on a relation between the decay constants of \rho-like J^{PC}=1^{--} vector mesons, which arises solely from the perturbative analysis of the VV, TT and VT correlators at order \alpha_s^0 in the large-N_c limit. We find…
We extract pole positions for the N(1535) and N(1650) resonances using two different models. The positions are determined from fits to different subsets of the existing $\pi N\to\pi N$, $\pi N\to\eta N$ and $\gamma p\to\eta p$ data and…
We calculate the form factors and the coupling constant in the $D^{*}D \rho $ vertex in the framework of QCD sum rules. We evaluate the three point correlation functions of the vertex considering both $ D $ and $ \rho $ mesons off--shell.…
We derive an estimate for the ratio of the rho mass and the pion decay constant from an analysis of vector and axial-vector two-point functions using large-Nc, lowest-meson dominance and the operator product expansion, in the chiral limit.…
We study the meson-baryon interaction with $J^P=1/2^-$ using the hidden-gauge Lagrangians and mixing pseudoscalar meson-baryon with the vector meson-baryon states in a coupled channels scheme with $\pi N$, $\eta N$, $K\Lambda$, $K\Sigma$,…
In this article, we analyze the vertex $D^*D^*\rho$ with the light-cone QCD sum rules. The strong coupling constant $g_{D^*D^*\rho}$ is an important parameter in evaluating the charmonium absorption cross sections in searching for the…
We report on the computation of the scaling of QCD observables with the number of colours, $N_c$. For this, we use dynamical configurations with four active flavours, $N_f=4$, and values of $N_c=3-6$. We study the meson masses and decay…
We show that information on the weak phase gamma can be extracted from the K* pi and rho K decays. Less hadronic uncertainty is involved when the observables of four of these modes are combined together. We further point out two approximate…
We investigate the $\sigma$ and $\rho$ coupling constants for the $DD$ and $D^*D^*$ interactions, based on correlated $2\pi$ exchange in the $DD$ and $D^*D^*$ interactions. Starting from the $D\bar{D}\to \pi\pi$ and $D^*\bar{D}^*\to \pi\pi$…
Using the recent precise measurements of eta photopro- duction in proton and deuteron targets, we extract the ratio of the helicity amplitudes A^n_1/2 / A^p_1/2, for the excitation of N^*(1535), in the effective Lagrangian approach, It is…
Using a chiral unitary model in which the negative parity nucleon resonance $N^\ast \equiv N^\ast(1535)$ is generated dynamically by means of the Bethe Salpeter equation with coupled meson baryon channels in the $S = 0$ sector, we have…
We report on the determination of the electrocouplings for the transition from the proton to the $N(1675){\frac{5}{2}}^-$ resonance state using recent differential cross section data on $e p \rightarrow e\pi^+ n$ by the CLAS collaboration…
Background: Until now the knowledge about nucleon resonances with a mass higher than 2 GeV has been scarce. Huge amounts of experimental data of the multipion photoproduction have been accumulated, and more can be expected in the future in…
In this article, we firstly analyze the mass and pole residue of negative parity nucleon $N^*(1535)$ within the two-point QCD sum rules. Basing on these results, we continuously study the strong coupling constants of vertices…
The form-factors for the transition $ N^*(1535)\to N $ induced by isovector and isoscalar axial currents within the framework of light-cone QCD sum rules by using the most general form of the interpolating current are calculated. In…
We investigate the parity-violating pion-nucleon-nucleon coupling constant $h^1_{\pi NN}$, based on the chiral quark-soliton model. We employ an effective weak Hamiltonian that takes into account the next-to-leading order corrections from…
The axial coupling and the magnetic moment of D*-meson or, more specifically, the couplings g(D*Dpi) and g(D*Dgamma), encode the non-perturbative QCD effects describing the decays D*-->Dpi and D*-->Dgamma. We compute these quantities by…
In the framework of the relativistic and gauge invariant spectral integral technique, we calculate radiative decays rho(770)-> gamma pi(140) and omega(780)-> gamma pi(140) supposing all mesons (pi, rho and omega) to be quark-antiquark…
We critically evaluate the isovector GMO sumrule for the charged $\pi N N$ coupling constant using recent precision data from $\pi ^-$p and $\pi^-$d atoms and with careful attention to systematic errors. From the $\pi ^-$d scattering length…
A novel extrapolation method has been used to deduce the charged Pion-Nucleon coupling constant from backward $np$ differential scattering cross sections. We applied it to new measurements performed at 162 MeV at the The Svedberg Laboratory…