Related papers: Baryon Resonances
We study the structure of the baryon resonances $\Lambda(1405)$ and $\bar\Lambda(1405)$ in $J/\psi$ four body decays $J/\psi\to \Sigma\bar \Sigma \pi\pi$ in the framework of a coupled channel chiral unitary approach. With still sufficient…
We report on the latests developments in the field of baryonic resonances generated from the meson-baryon interaction in coupled channels using a chiral unitary approach. The collection of resonances found in different strangeness and…
A vector meson exchange model based on effective Lagrangians is used to build the meson--baryon interaction in the charm $+1$, strangeness $-2$ and isospin $0$ sector. The s-wave scattering amplitudes resulting from the unitarization in…
Several recent experiments have reported evidence for a narrow baryon resonance with positive strangeness ($\Theta^+$) at a mass of 1.54 GeV/$c^2$. Baryons with $S=+1$ cannot be conventional $qqq$ states and the reports have thus generated…
We present results of meson and baryon spectroscopy using the Chirally Improved Dirac operator on lattices of size 16**3 x 32 with two mass-degenerate light sea quarks. Three ensembles with pion masses of 322(5), 470(4) and 525(7) MeV and…
We explore the possibility that some of the five narrow $\Omega_c$ resonances recently observed at LHCb could correspond to pentaquark states, structured as meson-baryon bound states or molecules. The interaction of the low-lying…
The extension of chiral theories to the description of resonances, via the incorporation of unitarity in coupled channels, has provided us with a new theoretical perspective on the nature of some of the observed excited hadrons. In this…
We suggest to classify baryon resonances as single-quark states in a mean field, and/or as its collective excitations. Identifying the Roper resonance N(1440), the nucleon resonance N(1535), and the singlet hyperon Lambda(1405) as…
All available data indicate a surplus of baryon states over meson states for energies greater than about 1.5 GeV. Since hadron-scale string theory suggests that their numbers should become equal with increasing energy, it has recently been…
Recent studies within the framework of chiral unitary theory produce the $\Lambda (1520)$ resonance, among several others, as a dynamically generated resonance from the interaction of the baryon decuplet and the meson octet. The $\Lambda…
As an example of dynamically generated resonances we mention the interaction of vector mesons with baryons within the local hidden gauge formalism which gives rise to a large amount of such states, many of which can be associated to known…
We have carried out a study of the $\gamma ~ p \rightarrow p K^{+} K^{*-} (K^{*-} \rightarrow K^{-} \pi^{0}) $, $ \gamma ~p \rightarrow p K^{+} K^{*-} ( K^{*-} \rightarrow \bar{K}^{0} \pi^{-} )$ and $ \gamma ~p \rightarrow K^{+} K^{-}p$…
In this talk I summarize recent findings around the description of axial vector mesons as dynamically generated states from the interaction of pseudoscalar mesons and vector mesons, dedicating some attention to the two $K_1(1270)$ states.…
The interaction between various charmed mesons and charmed baryons are studied within the framework of the coupled channel unitary approach with the local hidden gauge formalism. Several meson-baryon dynamically generated narrow $N^*$ and…
In these lectures I make an introduction to chiral unitary theory applied to the meson baryon interaction and show how several well known resonances are dynamically generated, and others are predicted. Two very recent experiments are…
The masses of fifteen baryon sets and twenty-four meson sets of three or more equal-quantum excited states are fitted by a simple two-parameter logarithm function, $M_n = \alpha Ln(n) + \beta$, where $n$ is the level of radial excitation.…
We have studied the $N^*(2120)$, $\Delta^*(1940)$, and the possible $\Sigma^*(1380)$ resonances in the $\gamma p \to K^+ \Lambda(1520)$, $pp \to n K^+ \Sigma(1385)$, and $\Lambda p \to \Lambda p \pi^0$ reactions within the resonance model…
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…
he observed well-known resonances $\Sigma^0$ $\Sigma^{*+}$(1385) and $K^{*\pm}$(892) from PDG are good tests of this method. Exotic strange multibaryon states have been observed in the effective mass spectra of: $\Lambda \pi^{\pm}$,$\Lambda…
Differential cross-section and single polarization observables in the process gamma p --> K^+ Lambda are investigated within a constituent quark model and a dynamical coupled-channel formalism. The effects of two new nucleon resonances and…