Related papers: Chiral approach to phi radiative decays
We introduce coupled channels of Bethe-Salpeter mesons both in the boundstate equation for mesons and in the mass gap equation for chiral symmetry. Consistency is insured by the Ward Identities for axial currents, which preserve the…
We construct an effective Lagrangian describing the interaction of soft pions and kaons with mesons containing a heavy quark and light degrees of freedom in an orbital $p$ wave. The formalism is easily extended to heavy mesons and baryons…
We study the four-body decays $J/\psi\to N {\bar N}$ {\it meson meson} using a chiral unitary approach to account for the meson meson final state interaction (FSI). The calculation of the $J/\psi\to N \bar N \pi^+ \pi^-$ process properly…
Underlying mixing of scalar mesons is studied in $\eta'\rightarrow \eta\pi\pi$ decay within a generalized linear sigma model of low-energy QCD which contains two nonets of scalar mesons and two nonets of pseudoscalar mesons (a…
Among the many unresolved questions in light quark spectroscopy, the underlying structure of the scalar mesons and the identification of states with a gluonic content rank high. Recently, new information has come from $\phi$ radiative…
In pure chiral perturbation theory (ChPT) the couplings of higher order Lagrangian terms are running parameters and hence can be determined only empirically from various low-energy hadronic processes. While this scenario works well for…
In this study, we investigate the $CP$-averaged branching fractions and direct $CP$ asymmetries in the quasi-two-body decays $B\to P (f_0(980) \to )(K^+K^-, \pi^+\pi^-)$ within the framework of perturbative QCD approach, where $P$ denotes…
We consider the radiative transition $\phi \to f_0 \gamma$, which is a sensitive probe of the nature of the $f_0(980)$ particle. Using the QCD sum-rule technique, we estimate the branching ratio of such decay mode to be: ${\cal B}(\phi \to…
In the SND experiment at the VEPP-2M electron-positron collider the PHI(1020)--->PI0+PI0+GAMMA decay was studied. The branching ratio B(PHI--->PI0+PI0+GAMMA)=(1.14+-0.10+-0.12)x10^{-4} was measured. It was shown, that the F0(980)GAMMA…
A phenomenological analysis of the scalar meson f0(980) is performed that relies on the quasi-two body decays D and Ds -> f0(980)P, with P=pi, K. The two-body branching ratios are deduced from experimental data on D or Ds -> pi pi pi, K…
We study the S-wave interaction of mesons with baryons in the strangeness S=0 sector in a coupled channel unitary approach. The basic dynamics is drawn from the lowest order meson baryon chiral Lagrangians. Small modifications inspired by…
We take an approach to the $\Lambda$ nonmesonic weak decay in nuclei based on the exchange of mesons under the guidelines of chiral Lagrangians. The one pion and one kaon exchange are considered, together with the exchange of two pions,…
Based on the effective Lagrangian approach, the $ J/\psi \to p \bar{p} \phi$ decay is studied in an isobar resonance model with the assumption that the $\phi$-meson is produced from intermediate nucleon resonances. The contributions from…
It has been commonly assumed that pseudoscalar contributions to the leptonic decay of charged mesons, like pions and kaons, is strongly constrained due to the helicity suppression present in the ratio $R_{l/l'} = \Gamma(P \rightarrow…
The dimensionless parameter $\xi' = M^2/(16 \pi^2 F^2)$, where $F$ is the pion decay constant in the chiral limit and $M$ is the pion mass at leading order in the quark mass, is expected to control the convergence of chiral perturbation…
We study the photoproduction of scalar mesons close to the threshold of f_0(980) and a_0(980) using a unitary chiral model. Peaks for both resonances show up in the invariant mass distributions of pairs of pseudoscalar mesons. A discussion…
The complementarity between Chiral Perturbation Theory and the Linear Sigma Model in the scalar channel is exploited to study $\pi^0\pi^0$ production in $\rho$ and $\omega$ radiative decays, where the effects of a low mass scalar resonance…
The nature of the light scalar mesons is one of the most intriguing open challenges in hadronic spectroscopy. It is argued that radiative decays involving these scalars can serve as an important decisive tool in establishing their nature.…
The N*(1440) -> N pi pi decay is studied by making use of the chiral reduction formula. This formula suggests a scalar-isoscalar pion-baryon contact interaction which is absent in the recent study of Hern{\'a}ndez et al. The contact…
Properties of scalar--isoscalar mesons in a mass range from pi-pi threshold up to 1800 MeV are analysed using an unitary model with separable interactions in three decay channels: pi-pi, K-anti K and an effective 2pi-2pi. Different…