A numerical analysis to the scalar form-factor in the ππ and KK coupled–channel system is made by solving the coupled-channel dispersive integral equations, using the iteration method. The solutions are found not unique. Physical application to the ππ central production in the pp → ppππ process is discussed based upon the numerical solutions we found. PACS numbers: 14.40.Aq; 11.55.Fv; 13.75.Lb ...

A numerical analysis to the scalar form-factor in the ππ and KK coupled–channel system is made by solving the coupled-channel dispersive integral equations, using the iteration method. The solutions are found not unique. Physical application to the ππ central production in the pp → ppππ process is discussed based upon the numerical solutions we found. PACS numbers: 14.40.Aq; 11.55.Fv; 13.75.Lb ...

A meson exchange model of the ππ interaction which fits free ππ scattering data is used to calculate the interactions of pions in nuclear matter as a function of nuclear density. Polarization of the nuclear medium by the pions results in a marked increase in the s-wave ππ attraction at low energy. The influence of this effect on the nucleon-nucleon interaction is a corresponding increase with d...

It is important to understand charmless three-body B decays to probe the standard model. These decays are sensitive to CP violation and supply information on strong interactions. To interpret in a reliable way weak decay observables it is important to take into account final state interactions between produced meson pairs. In the weak decays B → ππK [ 1, 2] one sees maxima around the ππ effecti...

We report the results from a study of the full sample of ∼ 6.031 × 10 K → πππ decays recorded by the NA48/2 experiment at the CERN SPS. As first observed in this experiment, the ππ invariant mass (M00) distribution shows a cusp-like anomaly in the region around M00 = 2m+, where m+ is the charged pion mass. This anomaly has been interpreted as an effect due mainly to the final state charge excha...

Interactions in coupled channels ππ, KK̄ and an effective 2π2π in scalar-isoscalar wave have been analysed. Influence of interchannel couplings on analytical structure of multichannel interaction amplitudes has been studied. Interplay of S-matrix zeroes and poles and their relation with parameters of scalar resonances has been investigated. PACS numbers: 11.80.Gw, 13.60.Le, 13.75.Lb, 14.40.Cs St...

B decays into ππK and KKK, where the ππ and KK pairs interact in isospin zero S-wave, are studied in the ππ effective mass range from threshold to 1.2 GeV. The interplay of strong and weak decay amplitudes is analyzed using an unitary ππ and KK coupled channel model. Final state interactions are described in terms of four scalar form factors constrained by unitarity and chiral perturbation theo...

B decays into ππK and KKK, where the ππ and KK pairs interact in isospin zero S-wave, are studied in the ππ effective mass range from threshold to 1.2 GeV. The interplay of strong and weak decay amplitudes is analyzed using an unitary ππ and KK coupled channel model. Final state interactions are described in terms of four scalar form factors constrained by unitarity and chiral perturbation theo...

We review results of an analysis of ππ interactions in S, P and D waves for two-pion effective mass from threshold to about 1.4 GeV. In particular we show a recent improvement of this analysis above the KK̄ threshold using more data for phase shifts and including the S0 wave inelasticity from ππ → KK̄. In addition, we have improved the fit to the f2(1270) resonance and used a more flexible P wave...