相关论文: The $\bar{p} p \to \phi \phi $ reaction in an effe…
A qualitative account of the meson-meson and meson-baryon interactions using chiral Lagrangians and the inverse amplitude method in coupled channels is done. The method, imposing exact unitarity, proves to be very useful tool to extend the…
It is shown that the reactions $e^+e^-\to\gamma\pi^0\pi^0(\eta)$ give a good chance for observing scalar $a_0$ and $f_0$ mesons. In the photon energy region less then 100 MeV the vector meson contributions $e^+e^-\to V^0\to\pi^0…
The temperature dependence of the $\phi$ meson mass and its decay width ($\phi \rightarrow K \bar{K}$)have been studied from an effective non-linear chiral Lagrangian in $SU(3)$. Effective mass has been obtained from the pole position of…
We present the first systematic investigation of the $S=-1$ meson--baryon interaction within a fully off-shell covariant unitarized chiral effective field theory framework up to next-to-leading order. In particular, we perform a detailed…
The meson meson interaction in the scalar isoscalar channel at finite baryonic density is studied in the framework of a chiral unitary approach which generates the f0 and sigma resonances and reproduces well the meson meson phase shifts in…
We calculate the shape of the $\pi\Sigma$ and $\bar K N$ invariant mass distributions in the $\Lambda_b \to J/\psi\, \pi\Sigma$ and $\Lambda_b \to J/\psi \,\bar K N$ decays that are dominated by the $\Lambda(1405)$ resonance. The weak…
The effective Lagrangian including one loop corrections is deduced for the couplings of the charged Higgs with quarks and leptons, and with charginos and neutralinos. The effect of the one loop corrections is found to be quite significant…
The cross-sections of the $\gamma p-\gamma' N'$, $\gamma p-\pi' N'$ and $\gamma p-\gamma'\pi' N'$ reactions are calculated in the framework of the field-theoretical one-particle ($\pi,\omega,\rho$-mesons, nucleon and $\Delta$-resonance)…
Starting from the Chiral Perturbation Theory Lagrangian, but keeping different masses for the charged and neutral mesons, and using a previously developed non-perturbative unitary scheme that generates the lightest meson-meson resonances,…
The reaction $\pi^{-}p \to \eta n$ is investigated within a dynamical coupled-channels model of meson production reactions in the nucleon resonance region. The meson baryon channels included are $\pi N$, $\eta N$, $\pi \Delta$, $\sigma N$,…
In this work, the production mechanisms of the hyperon resonances $\Lambda(1405)$ and $\Lambda(1520)$ in the $\pi^- p$ scattering are investigated within an effective Lagrangian approach incorporating Regge trajectories. By including…
The $SU(3)$ chiral effective lagrangian at next-to-leading order is applied to the S-wave meson-baryon interaction in the energy range around the $\eta N$ threshold. Potentials are derived from this lagrangian and used in a coupled channel…
We present here some results supporting the nature of the $\Lambda(1405)$ resonance as dynamically generated from the meson baryon interaction in coupled channels and resulting from the superposition of two close-by poles. We find support…
We study the process $J/\Psi \to \gamma \phi \omega$, measured by the BES experiment, where a neat peak close to the $\phi \omega$ threshold is observed and is associated to a scalar meson resonance around 1800 MeV. We make the observation…
In this talk I summarize recently proposed mechanisms to understand pi pi scattering to 1 GeV in an effective chiral Lagrangian. The Lagrangian includes higher resonances in addition to pions consistently with the chiral symmetry. Iso-spin…
A non-perturbative method which combines constraints from chiral symmetry breaking and coupled channel unitarity is used to describe the meson-meson interaction up to about 1.2 GeV. The approach uses the O(p^2) and O(p^4) chiral…
The $e^+e^- \to \omega \pi^0 \to \pi^0 \pi^0 \gamma$ process was investigated in the SND experiment at the VEPP-2M collider. A narrow energy interval near the $\phi$-meson was scanned. The observed cross-section reveals, at the level of…
A Regge approach to the reaction processes $\gamma p\to\pi^-\Delta^{++}$ and $\gamma p\to\pi^+\Delta^0$ is presented for the description of existing data up to $E_\gamma= 16$ GeV. The model consists of the $t$-channel…
We introduce an effective lagrangian including negative and positive parity heavy mesons containing a heavy quark, light pseudoscalars, and light vector resonances, with their allowed interactions, using heavy quark spin-flavour symmetry,…
The $pp \to nK^+\Sigma^+$ reaction is a very good isospin 3/2 filter for studying $\Delta^{++*}$ decaying to $K^+\Sigma^+$. With an effective Lagrangian approach, contributions from a previous ignored sub-$K^+\Sigma^+$-threshold resonance…