相关论文: Two pole structure of the Lambda(1405) resonance

The K^- p --> pi^0 pi^0 Sigma^0 reaction is studied within a chiral unitary model. The distribution of pi^0 Sigma^0 states forming the Lambda(1405) shows, in agreement with a recent experiment, a peak at 1420 MeV and a relatively narrow…

The $K^- p \to \pi^0 \pi^0 \Sigma^0$ reaction is studied within a chiral unitary model. The distribution of $\pi^0 \Sigma^0$ states forming the $\Lambda(1405)$ shows, in agreement with a recent experiment, a peak at 1420 MeV and a…

We use recent data on the $K^- p \to \pi^0 \pi^0 \Sigma^0$ reaction with the $\pi^0 \Sigma^0$ mass distribution of forming the $\Lambda(1405)$ with a peak at 1420 MeV and a relatively narrow width of $\Gamma = 38$ MeV, together with those…

We report on a recent theoretical work on the structure of the Lambda(1405) resonance within a chiral unitary approach, in which the resonance is dynamically generated in meson-baryon scattering. Studying the analytic structure of the…

We investigate the photoproduction of $K^*$ vector meson for the study of the $\Lambda(1405)$ resonance. The invariant mass distribution of $\pi\Sigma$ shows a different shape from the nominal one, peaking at 1420 MeV. This is considered as…

We evaluate theoretically the radiative decay widths into $\gamma\Lambda$ and $\gamma\Sigma^0$ of the two poles of the $\Lambda(1405)$ found in chiral unitary theories and we find quite different results for each of the two poles. We show…

We develop a model that describes the gamma p -> K^+ pi Sigma reaction in the Lambda(1405) region. The model consists of gauge invariant photo-production mechanisms, and the chiral unitary model that gives the rescattering amplitudes where…

We present a strategy to extract the position of the two $\Lambda(1405)$ poles from experimental photoproduction data measured recently at different energies in the $\gamma p \to K^+ \pi^0 \Sigma^0 $ reaction at Jefferson Lab. By means of a…

The Lambda(1405) resonance is studied by a chiral unitary approach, in which the resonance is dynamically generated in coupled-channel meson-baryon scattering. Investigating the analytic structure of the scattering amplitudes obtained by…

We have investigated the single-pole nature of the detectable Lambda(1405) in detail, by employing a chiral model having double poles of a KbarN-piSigma coupled channel T-matrix. The effects of the 1st pole and the 2nd pole on the observed…

Recent CLAS data for the pi Sigma invariant mass distributions (line-shapes) in the gamma p -> K^+ pi Sigma reaction are theoretically investigated. The line-shapes have peaks associated with the Lambda(1405) excitation. Our model consists…

We present here some results supporting the nature of the $\Lambda(1405)$ resonance as dynamically generated from the meson baryon interaction in coupled channels and resulting from the superposition of two close-by poles. We find support…

The nature of the Lambda(1405) is discussed based on the unitarised coupled-channels approach with chiral dynamics (chiral unitary model). This approach describes the Kbar N scattering cross sections and the Lambda(1405) spectra…

In this paper, we study the polarization of the $\Lambda(1405)$ in the $\gamma p \rightarrow K^+ \pi \Sigma$ reaction within an effective Lagrangian approach and isobar model. In our model, the $\Lambda(1405)$ is excited through the…

The pp -> p K+ Y0 reaction has been studied for hyperon masses m(Y0)<1540 MeV/c2 at COSY-Juelich by using a 3.65 GeV/c circulating proton beam incident on an internal hydrogen target. Final states comprising two protons, one positively…

We discuss the mechanisms that lead to $\Lambda(1405)$ production in the $\pi^-p\to K^0\pi\Sigma$ reaction. The problem has gained renewed interest after different works converge to the conclusion that there are two resonances around the…

We have studied the structure of K- pp by solving this system in a variational treatment, starting from ansatz that Lambda(1405) is a K-p quasi-bound state, Lambda* with mass 1405 MeV/c2. The structure of K-pp reveals a molecular feature,…

We have carried a theoretical study of the K^- p\to M B \gamma reaction with M B = K^-p, \bar{K}^0 n, \pi^- \Sigma^+, \pi^+ \Sigma^-, \pi^0 \Sigma^0, \pi^0 \Lambda, for K^- lab. momenta between 200 and 500 MeV/c, using a chiral unitary…

Three-body calculations of $K\bar{K}N$ system with quantum numbers $I=1/2$, $J^{\pi}=(\frac{1}{2})^{+}$ were performed. Using separable potentials for two-body interactions, we calculated the $\pi\Sigma$ mass spectra for the…

We present an analysis of the Lambda(1405) resonance produced in the reaction p+p->Sigma^{pm}+pi^{mp}+K+p at 3.5 GeV kinetic beam energy measured with HADES at GSI. The two charged decay channels Lambda(1405) -> Sigma^{\pm}+pi^{\mp} have…