Related papers: An update on the Kappa

Recent BES results on light scalars are reported in this talk, including the observation of a charged kappa decaying to K pi0 with 5.8 * 10^7 J/psi data at BES II and the direct measurements of a0(980)-f0(980) mixing in the processes J/psi…

The observation of the scalar meson, kappa(900) was reported in the fall of the last year in the analyses on the K pi system of the J/psi -> bar K^*(892)^0 K^+ pi^- decay data obtained by the BES collaboration. The analyses have been…

Using 385 fb^-1 of e^+e^- collisions at the CM energies of around 10.6 GeV recorded by the BaBar experiment, we study the amplitudes of the singly Cabibbo-suppressed decay D^0 --> K^- K^+ pi^0. We measure the strong phase difference between…

A new unitarization approach incorporated with chiral symmetry is established and applied to study the $\pi K$ elastic scatterings. We demonstrate that the $\kappa$ resonance exists, if the scattering length parameter in the I=1/2, J=0…

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…

Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement for the branching ratios of the Cabibbo-suppressed decay modes D0-->Pi-Pi+ and D0-->K-K+. We measured: Gamma(D0-->K-K+)/Gamma(D0-->Pi-Pi+) = 2.81 +/-…

As pointed out in previous studies, the measurement of the skewness of the convergence field $\kappa$ will be useful in breaking the degeneracy among the cosmological parameters constrained from weak lensing observations. The combination of…

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: $p\bar p ~(at~rest)\to \pi^0\pi^0\pi^0$,…

Low-energy data on the three charge states in $\gamma p \to K^+(\Sigma\pi)$ from CLAS at JLab, on $K^-p\to \pi^0\pi^0\Lambda$ and $\pi^0\pi^0\Sigma$ from the Crystal Ball at BNL, bubble chamber data on…

BES data on $J/\psi \to \gamma (K^+K^-\pi^+\pi^-)$ are presented. The $K^*\bar K^*$ contribution peaks strongly near threshold. It is fitted with a broad $0^{-+}$ resonance with mass $M = 1800 \pm 100$ MeV, width $\Gamma = 500 \pm 200$ MeV.…

We discuss the existence of the light scalar meson K^*_0(800) (also called kappa) in a rigorous way, by showing the presence of a pole in the pi K --> pi K amplitude on the second Riemann sheet. For this purpose, we study the domain of…

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 study the light scalar sector up to $1.8$ GeV by using a quantum field theoretical approach which includes a single kaonic state in a Lagrangian with both derivative and non-derivative interactions. By performing a fit to $\pi K$ phase…

The recent CLAS 2005, SAPHIR 2003, LEPS, and the old, pre-1972, data on K^+ Lambda photoproduction are compared with theoretical calculations in the energy region of E_gamma^lab < 2.6 GeV in order to learn about their mutual consistency.…

This paper is focused on two issues: the K\pi spectrum near threshold - the kappa problem -, and the pi\pi spectrum between 1.2 and 1.5 GeV/(c^2) -- the f_0(1370) problem. Both problems will be analysed from the perspective of the $D$ meson…

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…

A definite relative phase and amplitude exists between the doubly-Cabibbo-% suppressed amplitude for $D^0 \to \ko M^0$ and the Cabibbo-favored amplitude for $D^0 \to \ok M^0$, where $M^0 = (\pi^0,\eta,\eta')$: $A(D^0 \to \ko M^0) = - \tan^2…

The measurements of B -> pi K decays have been in disagreement with the predictions of the Standard Model (SM) for some time. In this paper, we perform an update of this puzzle using the latest (2008) data. We find that the situation has…

A new energy-dependent fit strategy, independent of any specific microscopic theory, is applied to kaon photoproduction data with center-of-mass energies ranging from 1625 MeV to 2296 MeV. Experimental data are fitted in terms of a modified…

Motivated by the $1/N_c$ expansion, we study a simple model in which the pi-K scattering amplitude is the sum of a current-algebra contact term and resonance pole exchanges. This phenomenological model is crossing symmetric and, when a…