Related papers: Further Analysis on \sigma-particle Properties
Re-analyzing the old phase shift data of I=0, \pi\pi (I=1/2, K\pi) scattering, we show an evidence for existence of the \sigma-particle (\kappa-particle) with a comparatively light mass, which has been missing for a long time: In the…
Recently we have shown an evidence for existence of \sigma-particle in the previous works; where the \pi\pi S-wave phase shift is reanalyzed, by introducing a repulsive background suggested by the chiral symmetry, and by applying a new…
Recently we obtained the evidence for the existence of sigma(600) meson, which had been sought but missing for a long time, by reanalyzing the I=0 S-wave pi pi scattering phase shift. The sigma-existence was also suggested through the…
We make a re-analysis of I=0 \pi\pi scattering phase shift \delta_0^0 through a new method of S-matrix parametrization (IA; interfering amplitude method), and show a result suggesting strongly for the existence of \sigma-particle --…
The evidences for sigma(600) and kappa(900) observed in our analyses on the pi pi and K pi scattering phase shift data are described, briefly. The analysis have been performed by the interfering amplitude method, which satisfies the…
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…
The analysis of the poles of the $\pi\pi$ scattering amplitude is shown to favour a dynamical origin of the sigma meson: it is created by a strongly attractive $\pi\pi$ interaction in the $J^{PC}=0^{++}I=0$ channel. In the limit…
We calculate the s-wave strong interaction $\Lambda$$\pi$ phase shift at the $\Xi$ mass taking into account contributions from the ${{\frac{1}{2}}}^{-}$ and ${{\frac{3}{2}}}^{-}$ $\Sigma$ resonances. We find the S-wave phase shift to be…
We investigate the determination of the pole associated to $\sigma$ from $\pi\pi$ scattering data below the $K\bar{K}$ threshold, including the new precise data from $K_{e4}$ decay reported recently by the NA48/2 Collaboration. Using a…
The results of the analysis of the pi^0 pi^0 scattering amplitudes obtained with pi^- P charge exchange reaction, pi^- P --> pi^0 pi^0 n, data at 9 GeV/c are presented. The pi^0 pi^0 scattering amplitudes show clear f_0(1370) and f_2(1270)…
Based on a sample of 7.8 million BESI $J/\psi$ events, the decay of $ J/\psi \to \omega \pi^+ \pi^-$ is studied. A low mass enhancement in the $\pi^+ \pi^-$ invariant mass spectrum recoiling against $\omega$ particle is clearly seen which…
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 present for the first time a determination of the energy dependence of the isoscalar $\pi\pi$ elastic scattering phase-shift within a first-principles numerical lattice approach to QCD. Hadronic correlation functions are computed…
The amplitude analysis has been performed on the pi0 pi0 final state obtained in the pi- p charge exchange process. The pi0 pi0 scattering amplitudes have been obtained for the S and D waves by the Chew-Low extrapolation and the partial…
The phenomenologically observed property of sigma(600) in our recent analyses of various pi pi-scattering and -production processes is reviewed and compared with the prediction of SU(2) linear sigma model. Furthermore, a possibility of the…
Studies on the IJ=00 $\pi\pi$ and $K\bar K$ coupled--channel system are made using newly derived dispersion relations between the phase shifts and poles and cuts. It is found that the $\sigma$ resonance must be introduced to explain the…
We improve, in the energy region between $\bar{K}K$ threshold and $\sim~1.4$ GeV, the energy-dependent phase shift analysis of $\pi\pi$ scattering presented in a previous paper. For the S0 wave we have included more data above $\bar{K}K$…
Recently, by reanalyzing the phase shift data of I=0 pipi$ and of I=1/2 Kpi scatterings, we showed the evidences for existence of light scalar mesons, sigma(600) and kappa(900), respectively, which had been sought but missing for a long…
The scalar-isoscalar pi-pi phase shifts are calculated in the pi-pi energy range from 600 MeV to 1600 MeV. We use results of the CERN-Cracow-Munich collaboration for the reaction pi^- p --> pi^+ pi^- n on a transversely polarized target at…
We discuss $\pi\pi$ scattering in the framework of chiral perturbation theory. In particular, we recall the predictions made some time ago for the threshold parameters and for the phase shift difference $\delta_0^0-\delta_1^1$.