相关论文: Sigma, Kappa, fo(980) and a0(980)

We revisit the coupled channel $K\bar{K}$ interactions and dynamically generate the resonances $f_0(980)$ and $a_0(980)$ within both the isospin and the physical bases. The $f_0(980)-a_0(980)$ mixing effects are generated in the scattering…

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…

We consider the issue of determining the D0-Dbar0 width difference Delta Gamma_D experimentally. The current situation is reviewed and suggestions for further study are given. We propose a number of D0 decay modes in addition to those…

The master formula approach to chiral symmetry breaking is used to analyze the phase shifts for $\pi\pi$ scattering in the elastic region. The results are in excellent agreement with the data for the phase shifts up to the K-K bar…

We study the two point-function for the scalar mesons $\sigma, \kappa, f_0(980)$ and $a_0(980)$ as diquak-antidiquark states. We also study the decays of these mesons into $\pi\pi$, $K\pi$ and $K\bar{K}$. We found that the couplings are…

We perform the analysis of the preliminary data on $e^+e^-\to\phi\to\gamma f_0(980)\to\gamma\pi^0\pi^0$ reaction simultaneously with the data on $\pi\pi$ scattering and reactions $J/\psi\to\phi\pi^+\pi^-$ and…

We make a study of the (pi^- p --> K^0 pi^0 Lambda), (pi^+ p --> K^+ pi^+ Lambda), (K^+\bar{K}^0 p), (K^+ pi^+ Sigma^0), (K^+ pi^0 Sigma^+), and (eta pi^+ p) reactions, in which the basic dynamics is given by the excitation of the…

The use of chiral perturbation theory in extracting physical K to pi pi matrix elements from matrix elements calculated at unphysical kinematics is outlined. In particular, the possibility of utilizing pions with non-zero momentum in the…

The prediction of the cross section $\sigma(\gamma\gamma^*(Q^2)\to \eta\pi^0)$ based on the simultaneous description of the Belle data on the $\gamma\gamma\to \eta\pi^0$ reaction and the KLOE data on the $\phi\to\eta\pi^0\gamma$ decay is…

A joint analysis of the pi+pi- and pi0pi0 S-wave amplitudes including results of three experiments has been performed. Using our theoretical model of the pion-pion production in which not only the pion exchange but also the a1(1260) meson…

We suggest a simple analytical description of the S-wave isoscalar $\pi\pi$ amplitude, which corresponds to a joint dressing of the bare resonance and background contributions. The amplitude describes well the experimental data on the…

Anomalous isotopic symmetry breaking in the $\eta(1405)\to f_0(980)\pi^0\to\pi^+\pi^-\pi^0$ decay through a mechanism featuring anomalous Landau thresholds in the form of logarithmic triangle singularities, i.e., through the $\eta(1405)\to…

Suggested by Au, Morgan, Pennington (AMP) S-wave isospin I=0 $\pi\pi$, $KK$ scattering amplitude is good enough to describe experimental data for the moment. Still it has two disadvantages for use in multiparticle partial wave analysis…

Based on an approach recently proposed by us, simultaneous $\chi^{2}$-analyses are performed for elastic scattering, direct reaction (DR) and fusion cross sections data for the $^{6}$He+$^{209}$Bi system at near-Coulomb-barrier energies to…

The measured rate for phi to gamma f0(980) appears to be larger than allowed on rather general grounds. We show that mixing between the f0(980) and a0(980), due to their dynamical interaction with the nearby KKbar thresholds, radically…

There has long been speculation about the nature of the $\sigma$-resonance. For three decades Jaffe has argued for a tetraquark composition, while others have claimed it is largely a glueball. A key pointer to its nature is its coupling to…

A partial wave analysis of the centrally produced pi+pi- channel has been performed in pp collisions using an incident beam momentum of 450 GeV/c. An unambiguous physical solution has been found. Evidence is found for the f0(980), f0(1300),…

Aims. We study the geometry and kinematics of the circumstellar environment of the Be star Kappa CMa in the Br gamma emission line and its nearby continuum. Methods. We use the VLTI/AMBER instrument operating in the K band which provides a…

In a combined analysis of the experimental data on the coupled processes $\pi\pi\to\pi\pi,K\bar{K}$ in the channel with $I^GJ^{PC}=0^+0^{++}$, the following results are obtained in a model-independent way: 1) The $f_0(665)$ state with…

We set up a general framework to describe $\pi\pi$ scattering below 1 GeV based on chiral low-energy expansion with possible spin-0 and 1 resonances. Partial wave amplitudes are obtained with the $N/D$ method, which satisfy unitarity,…