Related papers: Scalar meson exchange in phi->P0P0gamma decays

Decay amplitudes of D(D_s)->f0(980)X, X=pi, K, are compared to experimental branching ratios with the aim of singling out the poorly known D->f0(980) transition form factor in these amplitudes. Since the other elements of the amplitudes are…

Meson properties are considered within a U(3)\times U(3) Linear Sigma Model(LSM). The importance of the U_A(1)-breaking term and the OZI rule violating term in the generation of meson masses and mixing angles is stressed. The LSM parameters…

The scalar mesons f0(1370), f0(1500) and f0(1710) are of interest as there is as yet no consensus of their status, or indeed of the existence of the f0(1370). Radiative decays to rho and omega have been shown to provide effective probes of…

We study the line shapes of radiative $\phi$-decays involving virtual $f_{0}(980)$ and $a_{0}(980)$ mesons which decay, via derivative couplings, to $\pi^{0}\pi^{0}$ and $\pi^{0}\eta$ respectively. After developing the formalism for…

A sample of 1.25x10^9 phi decays, collected with the KLOE detector at the Frascati phi-factory DAFNE at center of mass energy ~ Mphi, has been used to study the radiative decay phi to eta pi0 gamma. This decay is dominated by phi to a0(980)…

The iso-singlet scalar resonance \sigma(600), found in the recent \pi\pi phase shift analysis, is pointed out to have the properties of the \sigma meson in the \sigma model. The role of the \lambda\phi^4 interaction as a source of the…

We discuss the role of meson exchange mechanisms in $\gamma \gamma \to \gamma \gamma$ scattering. Several pseudoscalar ($\pi^0$, $\eta$, $\eta'(958)$, $\eta_c(1S)$, $\eta_c(2S)$), scalar ($f_{0}(500)$, $f_0(980)$, $a_0(980)$, $f_0(1370)$,…

The scalar -- isoscalar pi-pi phase shifts are analysed using a separable potential model of three coupled channels (pipi, KK and an effective 2pi2pi system). Model parameters are fitted to two sets of solutions obtained in a recent…

We discuss scalar mesons properties on the light of chiral dynamics. Considering them as the chiral partners of pseudo-scalar mesons we propose an explanation to their unusual properties based on non-trivial vacuum effects coming from the…

In this work, we have investigated the process $D_s^+\to K^+ K^- \pi^+$, taking into account the contributions from the $S$-wave pseudoscalar-pseudoscalar interaction within the chiral unitary approach, and also the intermediate $\phi$…

New ongoing experimental activities that have direct reference to pi^0 decay modes call for a new theoretical study in this area. We will summarize some details and interesting facts that concern main decay modes of this lightest meson.

We present and discuss some experimental approaches involving spectroscopy from heavy meson decays going to light mesons. In particular we emphasis the scalar resonance $f_0(980)$, which have different well determined parameter of mass and…

Using the fact that the contribution of the states with isospin I=0 in the difference of the amplitudes of the processes \gamma \gamma->\pi^+\pi^- and \gamma\gamma->\pi^0\pi^0 is very small, we have analyzed the dispersion sum rules for the…

We study the $\chi_{c1} \to \eta \pi^+ \pi^-$ decay, paying attention to the production of $f_0(500)$, $f_0(980)$ and $a_0(980)$ from the final state interaction of pairs of mesons that can lead to these three mesons in the final state,…

The pion scalar form factor along with all existing S-wave iso-scalar $\pi\pi$-scattering phase shift data in the elastic region up to $1 {\rm GeV}^2$ are applied for a determination of the $f_0(500)$ and $f_0(980)$ meson parameters…

We have studied the phi->a_0(980) gamma process with the KLOE detector at the Frascati phi-factory DAPhNE by detecting the phi->eta pi^0 gamma decays in the final states with eta->gamma gamma and eta->pi^+ pi^- pi^0. We have measured the…

We first study the charmless two-body $\Lambda_b$ decays with the scalar mesons as the final states and predict that ${\cal B}(\Lambda_b\to \Lambda f_0(980,1500))=(2.9\pm 0.7,12.4\pm 3.8)\times 10^{-6}$ and ${\cal B}(\Lambda_b\to p…

We study the $\omega\to\pi\pi\gamma$ decays by adding to the amplitude calculated within the framework of chiral perturbation theory and vector meson dominance the amplitude of $\sigma$-meson intermediate state. We estimate the coupling…

We study the radiative decay $\rho^{0}\to\pi^{0}\pi^{0}\gamma$ within the framework of a phenomenological approach in which the contributions of $\sigma$-meson and $\omega$-meson intermediate states and of the pion-loops are considered. We…

The production and decay of vector mesons ($\rho, \omega$) in $pA$ reactions at COSY energies is studied with particular emphasis on their in-medium spectral functions. It is explored within transport calculations, if hadronic in-medium…