相关论文: Constraints on background contributions from K+ La…
The photoproduction p(gamma, K+)Lambda process is studied within a field-theoretic approach. It is shown that the background contributions constitute an important part of the reaction dynamics. We compare predictions obtained with three…
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…
Kaon photo- and electroproduction off the nucleon is investigated in the framework of an isobaric model up to energies of about 1 GeV above threshold for all six isospin channels. The hadronic coupling constants in the model are determined…
Background: In $\pi^+n$ and $\pi^-p$ electroproduction, conventional models cannot satisfactory explain the data above the resonance region, in particular the transverse cross section. Although no high-energy L-T-separated cross-section…
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…
The new experimental data of kaon photoproduction on the nucleon, gamma p -> K+ Lambda, have been analyzed by means of a multipoles model. Different from the previous models, in this analysis the resonance decay widths are constrained to…
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…
The few available data for the reactions $\gamma p \rightarrow K^{0} \Sigma^{+}$ and $\gamma n \rightarrow K^{+} \Sigma^{-}$ are compared to models developed for the processes $\gamma p \rightarrow K^{+} \Sigma^{0}$ and $\gamma p…
We present a Regge-plus-resonance (RPR) description of the p(e,e'K^+)Y processes (Y=\Lambda,\Sigma^0) in the resonance region. The background contributions to the RPR amplitude are constrained by the high-energy p(\gamma, K^+)Y data. As a…
The electroproduction of kaons on the nucleon is shown to be an ideal tool to extract electromagnetic form factors of strange mesons and hyperons. Longitudinal n(e,e'K0)Lambda cross sections are found to be sensitive to the K0 form factor,…
A microscopic approach has been employed to study the kaon and $\Lambda$ productions in heavy ion collisions. The productions of $K^+$ and $\Lambda$ have been studied within the framework of Boltzmann transport equation for various beam…
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…
Exploiting the isobar model, kaon photo- and electroproduction on the proton in the resonance region comes under scrutiny. An upgrade of our previous model, comprising higher-spin nucleon and hyperon exchanges in the consistent formalism,…
We discuss the role of hyperon resonances in the u-channel when modeling p (gamma,K+)Lambda processes in an effective Lagrangian approach. Without the introduction of hyperon resonances, one is forced to use soft hadronic form factors with…
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…
A dynamical coupled-channel formalism for processes $\pi N \to KY$ and $\gamma N \to KY$ is presented which provides a comprehensive investigation of recent data on the $\gamma p \to K^+ \Lambda$ reaction. The non-resonant interactions…
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…
The question of pseudovector versus pseudoscalar coupling schemes for the kaon-hyperon-nucleon interaction is re-examined for the reaction $\gamma p\to K^+ \Lambda$ in several isobaric models. These models typically include Born terms,…
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…
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…