Related papers: K*Lambda(1116) photoproduction and nucleon resonan…
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…
Isobar models for the electromagnetic production of kaons are discussed with emphasis on the K^+ photoproduction at very small kaon angles and K^0 photoproduction on deuteron. Distorted-wave impuls approximation calculations of the cross…
A coupled channel model with $\gamma N$, $KY$ and $\pi N$ channels has been used to analyze the recent data of $\gamma p \to K^+ \Lambda$. The non-resonant interactions within the subspace $KY \oplus \pi N$ are derived from effective…
Coherent pion electroproduction on the deuteron is studied in the $\Delta(1232)$ resonance region in the impulse approximation, i.e., neglecting pion rescattering and two-body effects. The elementary reaction on the nucleon is described in…
Eta photo- and electroproduction on the nucleon is studied using an isobar model. The model contains Born terms, and contributions from vector meson exchanges and nucleon resonances. Our results are compared with recent eta photoproduction…
We study the role of the nucleon resonances ($N^*$) in $\omega$ photoproduction by using the quark model resonance parameters predicted by Capstick and Roberts. The employed $\gamma N \to N^*$ and $N^* \to \omega N$ amplitudes include the…
Within an effective Lagrangian model, we present calculations for cross sections of the dilepton production in proton-proton and proton-neutron collisions at laboratory kinetic energies in 1-5 GeV range. Production amplitudes include…
We have investigated the role of hyperon resonances in the kaon photoproduction process, $\gamma p\to K^+\Lambda$, by using a covariant isobar model. To this end, new experimental data are used in the fitting process, whereas the old SAPHIR…
In this work, we study the charged-current (anti)neutrino-induced associated particle($K\Lambda$) production($\Delta S=0$) from free nucleons in the energy region of a few GeV, relevant to the (anti)neutrino oscillation experiments with…
We study the production of hyperon resonances in the $p\bar{p}\to\bar{\Lambda}\Sigma\eta$ reaction within an effective Lagrangian approach. The model includes the production of $\Sigma(1750)$ and $\Lambda(1670)$ in the intermediate state…
The $pp \to nK^+\Sigma^+$ reaction is a very good isospin 3/2 filter for studying $\Delta^{++*}$ decaying to $K^+\Sigma^+$. With an effective Lagrangian approach, contributions from a previous ignored sub-$K^+\Sigma^+$-threshold resonance…
Assuming that the $f'_2(1525)$ and $K^*_2(1430)$ resonances are dynamically generated states from the vector meson-vector meson interactions in $S$-wave with spin $S=2$, we study the $\gamma p \to f'_2(1525) p$ and $\gamma p \to K^*_2(1430)…
Some applications of the elementary kaon photoproduction process are discussed: the investigation of missing resonances in the p(gamma,K+)Lambda channel, the role of the P_{13}(1720) state in the p(gamma,K0)Sigma+ channel, and the…
The problem of extracting information on new and known $N^{*}$ resonances by fitting isobar models to photonuclear data is addressed. A new fitting strategy, incorporating a genetic algorithm, is outlined. As an example, the method is…
The J\"ulich-Bonn coupled-channel framework is extended to $K^+\Lambda$ photoproduction. The spectrum of nucleon and $\Delta$ resonances is extracted from simultaneous fits to several pion-induced reactions in addition to pion, eta and…
We investigate the electroproduction of eta mesons below a center of momentum energy of 1.6 GeV, with particular emphasis on the roles of the N*(1535) and N*(1520) resonances. Using the effective Lagrangian approach, we show that the…
We report calculations for exclusive pion photoproduction on nuclei beyond the first resonance region in the distorted wave impulse approximation. The elementary operator contains contributions from the resonances $P_{33}(1232)$,…
The $\gamma + p \rightarrow K^0 + \Sigma^+$ photoproduction reaction is investigated in the energy region from threshold to $E_\gamma = 2250$\,MeV. The differential cross section exhibits increasing forward-peaking with energy, but only up…
We report on the first results of a full three-body calculation of the $\bar{K}NN$-$\pi YN$ amplitude for the $K^-d\rightarrow\pi\Sigma n$ reaction, and examine how the $\Lambda(1405)$ resonance manifests itself in the neutron energy…
The pion- and photon induced reactions for the final states $\gamma N$, $\pi N$, $2\pi N$, $\eta N$, and $\omega N$ are studied within a coupled-channel effective Lagrangian approach in the energy region from the pion threshold up to 2 GeV.…