Related papers: Do we have three $S_{11}$ resonances in the second…
The recent Investigations in the chiral quark model show that kaon productions of nucleon play an important role in understanding the structure of baryons. The evidences of a third $S_{11}$ resonance in the second resonance region and two…
In this presentation, we report our recent studies on the $K^*\Lambda(1116)$ photoproduction off the proton target, using the tree-level Born approximation, via the effective Lagrangian approach. In addition, we include the nine (three- or…
The nucleon resonances near 2 GeV are investigated through the $\Sigma$(1385) and $\Lambda(1520)$ photoproductions within a Regge-plus-resonance approach based on the new experimental data released by the CLAS Collaboration. The…
Resonances with strong couplings to strangeness channels are investigated in a coupled-channels framework of kaon production with pions and photons. We find evidence for an additional D13 resonance around 1900 MeV that has a significant…
We analyze the electromagnetic production of K^+Lambda and K^0Lambda near their production thresholds by using isobar models. In the K^+Lambda channel we show that the model can nicely describe the available experimental data. In the…
Nucleon resonances are investigated through the electromagnetic production of K-mesons. We study the kaon photoproduction process at tree-level and compare to a recently developed unitary K-matrix approach. Employing hadronic form factors…
Kaon photo- and electroproduction off a proton near the production threshold are investigated by utilizing an isobar model. The background amplitude of the model is constructed from Feynman diagrams, whereas the resonance term is calculated…
We investigate kaon photoproduction off the neutron target, i.e., $\gamma n \to K^0 \Lambda$, focusing on the role of nucleon resonances given in the Review of Particle Data Group in the range of $\sqrt{s} \approx 1600 - 2200$ MeV. We…
An extensive and systematic study of the recent eta photoproduction data up to 1.2 GeV is presented within a chiral constituent quark model. A model embodying all known nucleonic resonances shows clear need for a yet undiscovered third S11…
We study the mechanism of the associated Lambda-kaon and Sigma-kaon production in nucleon-nucleon collisions over an extended range of near threshold beam energies within an effective Lagrangian model, to understand of the new data on pp…
We study the photoproduction of the $\Lambda(1405)$ and $\Sigma(1400)$ hyperon resonances, the latter of which is not a well established state. We evaluate the $s$-, $t$- and $u$-channel diagrams in the Born approximation by employing the…
Distinctive patterns are predicted by quenched quark models and unquenched quark models for the lowest SU(3) baryon nonet with spin parity $J^P=1/2^-$. While the quenched quark models predict the lowest $1/2^-$ $\Sigma^*$ resonance to be…
A unitary coupled-channel effective Lagrangian model is applied to the combined analysis of the $(\pi,\gamma) N \to K\Lambda$ reactions in the energy region up to 2 GeV. To constrain the resonance couplings to the $K\Lambda$ final state the…
An effective Lagrangian model in a coupled channels framework is applied to extract nucleon resonance parameters. In the K-matrix approximation, we simultaneously analyze all the available data for the transitions from pi N to five possible…
The $S$-wave $\Lambda K$ and $\Sigma K$ states with isospin $I=1/2$ are dynamically investigated within the framework of the chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from…
We analyze the $K^-p\to K^+\Xi^-$ and $K^-p\to K^0\Xi^0$ processes in the energy region $1.8<\sqrt{s}<2.8$ GeV within an effective Lagrangian approach. The $\Lambda(1800)$ and $\Sigma(2250)$ resonances, along with the ground states $\Sigma$…
Kaon photoproduction on the proton is studied in the resonance region using an isobar model. The higher-spin nucleon (3/2 and 5/2) and hyperon (3/2) resonances were included in the model utilizing the consistent formalism by Pascalutsa and…
Photo- and electroproduction of $K\Sigma$ have been investigated near their production thresholds by using an effective Lagrangian approach. For this purpose, the background amplitude is constructed from suitable Feynman diagrams, whereas…
We identify the leading s-wave amplitudes of the SU(3) chiral meson-baryon Lagrangian with an effective coupled-channel potential which is iterated in a Lippmann-Schwinger equation. The strangeness $S=-1$ resonance $\Lambda(1405)$ and the…
The meson photoproductions off nucleons in the chiral quark model are described. The role of the S-wave resonances in the second resonance region is discussed, and it is particularly important for the Kaon, $\eta$ and $\eta'$…