Related papers: Chiral loop and LsigmaM predictions for phi->pi0et…

The complementarity between Chiral Perturbation Theory and the Linear Sigma Model is exploited to study scalar meson exchange in V->P0P0gamma decays. The recently reported experimental data on phi->pi0pi0gamma, phi->pi0etagamma and…

A consistent description of $\sigma(500)$ meson effects in $\rho^0\to\pi^0\pi^0\gamma$ and $\pi^+\pi^-\gamma$ decays is proposed in terms of reasonably simple amplitudes which reproduce the expected chiral-loop behaviour for large…

In an attempt to explain the latest experimental result about the branching ratio of $\omega\to \pi^0\pi^0\gamma$ decay we reexamine the decay mechanism of this decay in a phenomenological framework in which the contributions of VMD, chiral…

We study the effect of scalar-isoscalar $f_{0}(980)$ meson in the mechanism of the radiative $\phi\to \pi^{+}\pi^{-}\gamma$ decay. A phenomenological approach is used to study this decay by considering the contributions of $\sigma$-meson,…

We show that therecently observed pion invariant mass distribution of the phi ->pi0 pi0 gamma decay can be satisfactorily described by the chiral U(3) X U(3) Linear Sigma Model.

We have previously analysed the chiral predictions for the decay K_L -> pi0 gamma e+ e- and discussed how experimental measurements of this process can help our understanding of chiral theories and of CP tests. Motivated by the possibility…

The $\phi \to \omega \pi^0$ decay is studied using the method of phenomenological chiral Lagrangians. It is shown that the weak hadronic current between $\omega$-and $\pi^0$ -mesons is equal to zero and this decay channel proceeds only due…

The importance of resonances for the radiative hyperon decays is examined in the framework of chiral perturbation theory. Low lying baryon resonances are included into the effective theory and tree contributions to these decays are…

The radiative decays $V\to S\gamma$ and $S\to V\gamma$ with $V=\rho, \omega, \phi$ and $S=a_0, \sigma, f_0$ are calculated within the framework of the Linear Sigma Model. Current experimental data on the $\phi\to f_0\gamma$ and…

In this work, we analyze the semi-leptonic decays $\bar B^0/D^0 \to (a_0(980)^{\pm}\to\pi^{\pm}\eta) l^{\mp} \nu$ within light-cone sum rules. The two and three-body light-cone distribution amplitudes (LCDAs) of the $B$ meson and the only…

In view of the recent experimental developments on the experimental side in the $\eta \to \pi^0 \gamma \gamma$ decay, and the fact that the Particle Data Group in the on line edition of 2007 reports sizable changes of the radiative decay…

A chiral field theory of mesons has been applied to study the contribution of the current quark masses to the $\pi^0\rightarrow\gamma\gamma$ decay width at the next leading order. $2\%$ enhancement has been predicted and there is no new…

We study the effect of the sigma(600) and a_1(1260) resonances in the rho^0 -> pi^+ pi^- gamma decay, within the meson dominance model. Major effects are driven by the mass and width parameters of the sigma(600), and the usually neglected…

The features of the Resonance Chiral Theory (RChT) related to the description of the lightest scalar resonances, sigma, f0(980) and a0(980), are discussed. Major attention is paid to the fits of the invariant mass distributions in the…

The following topics are considered. 1) Confinement, chiral dynamics, and light scalar mesons. 2) Chiral shielding of the $\sigma(600)$. 3) The $\phi$ meson radiative decays about nature of light scalar resonances. 4) The $J/\psi$ decays…

Recently, the Belle Collaboration has measured the $\Lambda_c^+ \to \eta \Lambda \pi^+$ decay and reported the $\eta\Lambda$ and $\Lambda\pi^+ $ invariant mass distributions, which show the clear signals of the resonances $\Lambda(1670)$…

The dimensionless parameter $\xi = M_\pi^2/(16 \pi^2 F_\pi^2)$, where $F_\pi$ is the pion decay constant and $M_\pi$ is the pion mass, is expected to control the convergence of chiral perturbation theory applicable to QCD. Here we…

Radiative decays \phi\to\eta\pi^0\gamma and \phi\to\pi^0\pi^0\gamma are studied assuming that these decays are caused through the intermediate a_0(980)\gamma and f_0(980)\gamma states, respectively. Fitting the experimental data of the…

We study different types of radiative decays involving f0(980) and a0(980) mesons within a unified ChPT-based approach at one-loop level. Light scalar resonances which are seen in pi pi, pi eta, K K-bar channels of phi(1020) radiative…

We investigate the rare radiative eta decay modes $\eta\to\pi^+\pi^-\gamma\gamma$ and $\eta\to\pi^0\pi^0\gamma\gamma$ within the framework of chiral perturbation theory at $O(p^4)$. We present photon spectra and partial decay rates for both…