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We investigate $phi$ meson photoproduction on the nucleon and the uclide[4]{He} targets within a dynamical model approach based on a Hamiltonian which describes the production mechanisms by the Pomeron-exchange, meson-exchanges, $phi$ radiations, and nucleon resonance excitations mechanisms. The final $phi N$ interactions are included being described by the gluon-exchange, direct $phi N$ couplings, and the box-diagrams arising from the couplings with $pi N$, $rho N$, $KLambda$, and $KSigma$ channels. The parameters of the Hamiltonian are determined by the experimental data of $gamma p to phi p$ from the CLAS Collaboration. The resulting Hamiltonian is then used to predict the coherent $phi$-meson production on the uclide[4]{He} targets by using the distorted-wave impulse approximation. For the proton target, the final $phi N$ rescattering effects, as required by the unitarity condition, are found to be very weak, which supports the earlier calculations in the literature. For the uclide[4]{He} targets, the predicted differential cross sections are in good agreement with the data obtained by the LEPS Collaboration. The role of each mechanism in this reaction is discussed and predictions for a wide range of scattering angles are presented, which can be tested in future experiments.
The isobar model EtaMAID has been updated with new and high precision data for eta and etaprime photoproduction on protons and neutrons from MAMI, ELSA, GRAAL and CLAS. The background is described in a recently developed Regge-cut model, and for the
We investigate the reaction mechanism of the $phi$-meson photoproduction off the proton target, i.e., $gamma ptophi p$, up to $sqrt{s}=2.8$ GeV. For this purpose, we employ an effective Lagrangian approach in the tree-level Born approximation, and we
We compute dilepton invariant mass spectra from the decays of rho mesons produced by photon reactions off nuclei. Our calculations employ a realistic model for the rho photoproduction amplitude on the nucleon which provides fair agreement with measur
We study $eta$ photoproduction off the deuteron ($gamma dtoeta pn$) at a special kinematics: $sim 0.94$ GeV of the photon beam energy and $sim 0^circ$ of the scattering angle of the proton. This kinematics is ideal to extract the low-energy $eta$-nuc
Using a relativistic effective Lagrangian at the hadronic level, near-threshold $omega$ and $phi$ meson productions in proton proton ($pp$) collisions, $p p to p p omega/phi$, are studied within the distorted wave Born approximation. Both initial and