相关论文: Finite-Energy Sum Rules in Eta Photoproduction off…

The $\gamma N \to \pi^0 N$ and $\gamma N \to \eta N$ reactions at photon beam energies above 4 GeV are investigated within Regge models. The models include $t$-channel exchanges of vector ($\rho$ and $\omega$) and axial vector ($b_1$ and…

Very recent data for the reaction gamma{d} --> eta{np} are analyzed within a model that includes contributions from the impulse approximation and next order corrections due to the np and eta{N} interactions in the final state. Comparison…

We present results of a recent work on the reaction mechanism of $\eta n$ photoproduction off the neutron in the range of $ \sqrt{s} \approx 1.5 - 1.9$ GeV and discuss the role of various nucleon resonances listed in the Particle Data Group…

A microscopic four-body description of near-threshold coherent photoproduction of the $\eta$ meson on the (3N)-nuclei is given. The photoproduction cross-section is calculated using the Finite Rank Approximation (FRA) of the nuclear…

An analysis of incoherent photoproduction of $\eta$ mesons off the deuteron for photon energies from threshold to 800 MeV is presented. The dominant contribution, the $\gamma$N-$\eta$N amplitude, is described within an isobar model. Effects…

Very recent data for the reaction gamma+d ->eta np, namely total cross sections, angular and momentum spectra, are analyzed within a model that includes contributions from the impulse approximation and next order corrections due to the np…

The questions on the presense and quantitative role of the constant terms in the real part of the high-energy photon-nucleon and photon-nucleus amplitudes representing the contribution of the non-Regge (the fixed j=0-pole) singularities in…

We investigate $\eta$ photoproduction off the neutron target, i.e., $\gamma n \to \eta n$, employing an effective Lagrangian method combining with a Regge approach. As a background, we consider nucleon exchange in the $s$-channel diagram…

We report on the measurement of the beam asymmetry $\Sigma$ for the reactions $\vec{\gamma}p\rightarrow p\eta$ and $\vec{\gamma}p \rightarrow p\eta^{\prime}$ from the GlueX experiment, using an 8.2--8.8 GeV linearly polarized tagged photon…

A reggeized model for \eta and \eta' photoproduction on the nucleon is presented. In this model, t-channel vector meson exchanges are described in terms of Regge trajectories to comply with the correct high energy behavior. We compare this…

A relativistic model for the quasifree photoproduction of eta meson from complex nuclei is developed. The interactions between fields are introduced through effective Lagrangians. Contributions from several nucleon resonances as well as…

The recent high-precision data for the reaction $\gamma p\to p\eta'$ at photon energies in the range 1.5--2.3 GeV obtained by the CLAS collaboration at the Jefferson Laboratory have been analyzed within an extended version of the…

Eta photo- and electroproduction off the nucleon is investigated in an effective lagrangian approach that contains Born terms and both vector meson and nucleon resonance contributions. In particular, we review and develop the formalism for…

For the spectroscopy of nucleon resonances at the total energies from the $\eta^\prime$-meson production threshold to $2.32$ $\mathrm{GeV}$, photon beam asymmetries of the reaction $\gamma p \to \eta^\prime p$ were measured together with…

Photoproduction of $\eta$ mesons off $^{12}$C, $^{40}$Ca, $^{93}$Nb, and $^{nat}$Pb nuclei has been measured with a tagged photon beam with energies between 0.6 and 2.2 GeV. The experiment was performed at the Bonn ELSA accelerator with the…

We investigate the $\eta'$ photoproduction off the nucleon with a particular interest in the effect of the final-state interaction (FSI) of the $\eta'$ meson and nucleon $(\eta'N)$ based on three-flavor linear sigma model. We find an…

By working out the Bethe sum rule, a boundary condition that takes the form of a linear equality is derived for the fine structure observed in ionization edges present in electron energy-loss spectra. This condition is subsequently used as…

A microscopic few-body description of near-threshold coherent photoproduction of the eta-meson on tritium and He3 targets is given. The photoproduction cross-section is calculated using the Finite Rank Approximation (FRA) of the nuclear…

Adequate description of electro and gamma nuclear physics is of utmost importance in studies of electron beam-dumps and intense electron beam accelerators. I also is mandatory to describe neutron backgrounds and activation in linear…

We accomplish our efforts to obtain predictions for all four-fermion final states of e+ e- annihilation and the corresponding bremsstrahlung reactions which are possible in the framework of the Standard Model. For this purpose we have…