相关论文: The Kappa in J/Psi -> Kpplus-piminus-Kminus-piplus

Using a sample of 3.8 M psi(2S) events accumulated with the BES detector, the process psi(2S) -> pi^+ pi^- J/psi is studied. The angular distributions are compared with the general decay amplitude analysis of Cahn. We find that the dipion…

BES II data for the channel J/Psi -> gamma (piplus-piminus-piplus-piminus) are analysed from a sample of 58M J/Psi hadronic interactions. They reveal further detail in the J^{PC} = 0^{-+} sector for the 4pi channel. A broad 0^{-+} ->…

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…

Peculiarities of obtaining parameters for broad multi-channel resonances from data are discussed analyzing the experimental data on processes $\pi\pi\to\pi\pi,K\bar{K}$ in the $I^GJ^{PC}=0^+0^{++}$ channel in a model-independent approach…

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 $\bar{K}K$…

We present that there should exist a light strange-scalar meson kappa', in addition to the kappa(800), which has a mass around 1.1-1.2 GeV, a rather narrow width, and couples strongly to kappa(800)sigma(600) (Kpipipi) but weakly to Kpi,…

We simulate K pi scattering in s-wave and p-wave for both isospins I=1/2, 3/2 using quark-antiquark and meson-meson interpolating fields. We extract the elastic phase shifts delta at several values of the K-pi relative momenta. The…

New data are presented on $J/\psi \to \omega K^+K^-$ from a sample of 58M $J/\psi$ events in the upgraded BES II detector at the BEPC. There is a conspicuous signal for $f_0(1710) \to K^+K^-$ and a peak at higher mass which may be fitted…

We use our former results on pi+pi- S-wave obtained in a nearly assumption-free way from the 17.2 GeV/c data to predict the pi0pi0 S--wave. The predictions are compared with the recent results of the E852 experiment at 18.3 GeV/c. A good…

Coupled-channel $\pi K$ and $\eta K$ scattering amplitudes are determined by studying the finite-volume energy spectra obtained from dynamical lattice QCD calculations. Using a large basis of interpolating operators, including both those…

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 $\pi\pi$ scattering amplitude with regular analytical properties in the $s$ complex plane has been constructed. It describes simultaneously the data on the $\pi\pi$ scattering, $\phi\to\pi^0\pi^0\gamma$ decay and $\pi\pi\to K\bar K$…

We match the known chiral perturbation theory representation of the pi pi scattering amplitude to two loops with a phenomenological description that relies on the Roy equations. On this basis, the corrections to Weinberg's low energy…

Motivated by the presence of nearby thresholds in other baryon-meson channels with I=1 and S=-1, we investigate whether the Lambda pi scattering phase shifts at a center-of-mass energy equal to the Xi mass could be larger than suggested by…

A partial wave analysis is presented of $J/\psi \to \phi \pi ^+\pi ^-$ and $\phi K^+K^-$ from a sample of 58M $J/\psi$ events in the BES II detector. The $f_0(980)$ is observed clearly in both sets of data, and parameters of the Flatt\' e…

Based on the analysis of 6.031*10^7 K+- --> pi0 pi0 pi+- decays, the NA48/2 collaboration has recently determined the S-wave pi-pi scattering lengths a_0-a_2 with high precision. In addition, the scattering length a_2 has been independently…

Results are presented on J/psi radiative decays to pi^+pi^- and pi^0pi^0 based on a sample of 58M J/psi events taken with the BESII detector. Partial wave analyses are carried out using the relativistic covariant tensor amplitude method in…

We present a determination of the isospin-1/2 elastic $\pi K$ scattering amplitudes in S and P partial waves using lattice Quantum Chromodynamics. The amplitudes, constrained for a large number of real-valued energy points, are obtained as…

K-matrix analysis of the $00^{++}$ wave is performed in the channels $\pi\pi,~K\bar K,~\eta\eta$ and $4\pi$ in the mass region up to 1550 MeV. The fit is based on the following data: $p\bar p ~(at~rest)\to \pi^0\pi^0\pi^0$,…

We present the complete differential decay rates for the process B_s -> J/psi K^+ K^- including S-wave and P-wave angular momentum states for the K^+ K^- meson pair. We examine the effect of an S-wave component on the determination of the…