相关论文: Nucleon resonances in the $\gamma p \to \phi K^+ \…
The $\Lambda(1520)$ resonance has been recently studied in a unitarized coupled channel formalism with $\pi\Sigma(1385)$, $K\Xi(1530)$, $\bar{K}N$ and $\pi\Sigma$ as constituents blocks. We provide a theoretical study of the predictions of…
The s-wave meson-nucleon interaction in the S=-1 sector is studied by means of a coupled-channel Lippmann Schwinger equation, using the lowest order chiral Lagrangian and a cut off to regularize the loop integrals. The position and width of…
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…
The production of eta' mesons in photon- and hadron-induced reactions has been revisited in view of the recent additions of high-precision data to the world data base. Based on an effective Lagrangian approach, we have performed a combined…
The excitations of nucleon resonances with hidden charm, $N^*_{c\bar{c}}$, in the $\gamma p$ reactions are investigated by using the predictions from the available meson-baryons (MB) coupled-channel models. For the $\gamma\,p\rightarrow…
The elementary production cross sections $\pi \Delta \rightarrow Y K$ $(Y=\Sigma,\,\, \Lambda)$ and $\pi N \rightarrow Y K$ are needed to describe kaon production in heavy ion collisions. The $\pi N \rightarrow Y K$ reactions were studied…
We investigate the cross section for the reaction $NN \to NNa_0$ near threshold and at medium energies. An effective Lagrangian approach with one-pion exchange is applied to analyze different contributions to the cross section for different…
We investigate the $a_2(1320)$ meson photon production in the $\gamma p \to n a^+_2(1320)$ and $\gamma p \to n \rho^0 \pi^+$ reactions within the effective Lagrangian method. For $\gamma p \to n a^+_2(1320)$ reaction, by considering the…
A recently developed nonperturbative chiral approach to describe the S=-1 meson-baryon reactions has been extended to investigate the near threshold $K^- p \to \gamma \Lambda, \gamma \Sigma^0$ reactions. With the parameters governed by…
We study the reactions $\gamma\gamma\rightarrow \pi^0\pi^0$, $\pi^+\pi^-$, $K^0\bar{K}^0$, $K^+K^-$, $\eta \eta$ and $\pi^0\eta$ based on a chiral Lagrangian with dynamical light vector mesons as formulated within the hadrogenesis…
In a resonance model the reactions pi N -> Y K and pi Delta -> Y K are studied. For the reactions pi N -> Lambda K and pi Delta -> Lambda K, the resonances N(1650)(J^P=1/2^-), N(1710)(1/2^+) and N(1720)(3/2^+) are included as intermediate…
A chiral quark-model approach is adopted to study the $\gamma p\rightarrow \eta'p$ and $\gamma n\rightarrow \eta' n$. Good descriptions of the recent observations from CLAS and CBELSA/TAPS are obtained. Both of the processes are governed by…
Recent experimental results for the reaction \gamma + p \to K^+ + \Sigma + \pi\ from CLAS at Jefferson Lab are discussed. It was found that the mass distributions or "line shapes" of the three charge combinations \Sigma^+ \pi^-, \Sigma^0…
We investigate Lambda(1520,3/2^-,D_03) photoproduction via the gamma N -> K Lambda^* reaction process. Using effective Lagrangians, we compute the total and differential cross sections as well as the dependence on the momentum transfer for…
In this work, an improved quark model approach to the $\omega$ meson photo-production with an effective Lagrangian is presented. The {\it t}-channel {\it natural}-parity exchange is taken into account through the Pomeron exchange, while the…
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…
We present in this talk recent investigations on the nucleon-like resonance N*(1675) newly found in eta photoproduction by the GRAAL, Tohoku LNS-gamma and CB-ELSA collaborations. We focus on the production mechanism of the N*(1675),…
We perform a calculation of the cross section for nine reactions induced by $\bar K$ scattering on protons. The reactions studied are $K^-p \to \Lambda \pi^+ \pi^-$, $K^-p \to \Sigma^0 \pi^+ \pi^-$, $K^-p \to \Lambda \pi^0 \eta$, $K^-p \to…
The cross sections for the $p p \to p p \eta$ reaction are evaluated at energies relevant for the HADES, PANDA, and SIS100 experiments at GSI-FAIR. Consideration includes the $\eta$-bremsstrahlung mechanism involving intermediate proton…
Neutral current photon emission reactions with nucleons and nuclei are studied. These processes are important backgrounds for nu_mu to nu_e (bar(nu)_mu to bar(nu)_e) appearance oscillation experiments where electromagnetic showers…