Related papers: From known to undiscovered resonances
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…
The role of dynamics in spin observables for pseudoscalar meson photoproduction is investigated using a density matrix approach in a multipole truncated framework. Extraction of novel rules for $\gamma p \rightarrow \pi^+ n,~ K^+ \Lambda$…
New kaon photoproduction data on a proton, gamma + p --> K+ + Lambda, are analyzed using a multipole approach. The background terms are given in terms of gauge invariant, crossing symmetric, Born diagrams with hadronic form factors, while…
The study of hyperon resonances has entered a new era of precision with advent of high-statistics photoproduction data from the CLAS detector at Jefferson Lab. These data have multi-particle final states, allowing clean identification of…
Results for the reaction gamma p --> K+ Lambda, studied within a constituent quark model and a dynamical coupled-channel approach, are presented and compared with recent data. Issues related to the search for missing baryon resonances are…
In this talk I show recent results on how many excited baryon resonances appear as systems of one meson and one baryon, or two mesons and one baryon, with the mesons being either pseudoscalar or vectors. Connection with experiment is made…
We consider the reactions gamma p --> M B, with M B being either K+ Lambda, K+ Sigma0, or Pi n, within a diquark model which is based on perturbative QCD. The model parameters and the quark-diquark distribution amplitudes of the baryons are…
Within a chiral constituent quark formalism, allowing the inclusion of all known resonances, a comprehensive study of the recent eta photoproduction data on the proton up to 2 GeV is performed. This study shows evidence for a new S11…
The electromagnetic form factors of strange mesons and baryons are studied by means of kaon electroproduction on the nucleon. The response functions that are sensitive to the K0, Lambda, Sigma, and KK*\gamma transition form factors are…
Experiments with electromagnetic probes are promising to search for baryon resonances that have been predicted by quark models but have not yet been observed. Data sets from different experiments show interesting resonance structures…
One of the remaining challenges within the standard model is to gain a good understanding of QCD in the non-perturbative regime. A key step towards this aim is baryon spectroscopy, investigating the spectrum and the properties of baryon…
In this talk I review recent advances on the structure of the meson and baryon resonances which can be dynamically generated from the interaction of mesons or mesons and baryons. Particular emphasis is put on results involving vector…
We review recent progress in our understanding of the nucleon excitation spectrum. Thanks to dedicated efforts at facilities such as ELSA, MAMI and Jefferson Lab, several new nucleon resonances have been discovered, and evidence for…
In this talk I report on recent work related to the dynamical generation of baryonic resonances, some made up from pseudoscalar meson-baryon, others from vector meson-baryon and a third type from two meson-one baryon systems. We can…
We analyze the reactions gamma+p => M+B, with M B being either K+ Lambda, K+ Sigma0, or pi+ n, within perturbative QCD, allowing for diquarks as quasi-elementary constituents of baryons. The diquark-model parameters and the quark-diquark…
Within a chiral constituent quark model approach, $\eta$-meson production on the proton {\it via} electromagnetic and hadron probes are studied. With few parameters, differential cross-section and polarized beam asymmetry for \gamma p \to…
Experiments that study the hadronic and electromagnetic production of the pseudoscalar mesons -- pions, etas and kaons, contribute to our knowledge of the properties of baryon and hyperon resonances. Fixed-target programs at hadronic…
In this paper, we first review the theoretical and experimental studies of the process $\Lambda_c^+ \to \pi^+ \eta \Lambda$. Motivated by the recent BESIII and Belle measurements, we have conducted a theoretical study of the process…
The composite nature of baryons manifests itself in the existence of a rich spectrum of excited states, in particular in the important mass region 1-2 GeV for the light-flavoured baryons. The properties of these resonances can be identified…
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…