Study of deuteron-proton backward elastic scattering at intermediate energies

We study deuteron- proton elastic scattering in the deuteron energy range between 500 MeV and 2 GeV at the cms scattering angle \theta^*\ge 140^\circθ*≥140∘. The reaction is considered in the relativistic multiple scattering expansion framework. The four reaction mechanisms are included into consideration: one-nucleon exchange, single scattering, double scattering, and the term corresponding to the delta excitation in the intermediate state.The model is applied to describe the angular dependence of the differential cross section at the deuteron energies of between 880 and 1300 MeV. Also the energy dependence of the differential cross section and polarisation observables such as tensor analyzing power T_{20}T20 and polarization transfer from the deuteron to proton \varkappa𝜘 are considered at the scattering angle equal to 180^\circ∘. Contributions of the different reaction mechanisms into the reaction amplitude are demonstrated in comparison with the existing experimental data.

Nucleon Resonances in the Photoproduction γp → K∗+Λ

The differential cross-section data from the CLAS Collaboration for [Formula: see text] have been analyzed based on an effective Lagrangian approach. The [Formula: see text]-channel [Formula: see text], [Formula: see text], [Formula: see text] exchanges, the [Formula: see text]-channel [Formula: see text] and near-threshold [Formula: see text]’s exchanges, the [Formula: see text]-channel [Formula: see text], [Formula: see text], [Formula: see text] exchanges, and the generalized contact term are considered in constructing the reaction amplitude. It is found that by including the [Formula: see text] resonance, which is responsible for the shape of the angular distribution of [Formula: see text] near the [Formula: see text] threshold, and one of the [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] resonances, one can describe the cross-section data for this reaction reasonably well. More experimental data on spin observables are needed to further pin down the resonance contents and associated resonance parameters in this reaction.

STATUS OF MESON PHOTOPRODUCTION EXPERIMENTS WITH CLAS

A large part of the experimental program in Hall B of the Jefferson Lab is dedicated to baryon spectroscopy. Meson photoproduction experiments are essential part of this program. CEBAF Large Acceptance Spectrometer (CLAS) and availability of circularly and linearly polarized tagged photon beams in combination with longitudinally and transversely polarized frozen spin targets provide unique conditions for this type of experiments. For the first time, a complete or nearly complete measurement became possible and will allow model independent extraction of the reaction amplitude. The measurements were complete with both proton and deuteron targets. An overview of the collected experimental data will be presented.

RESCATTERING EFFECTS IN DEUTERON-PROTON ELASTIC SCATTERING AT INTERMEDIATE ENERGIES

The deuteron-proton elastic scattering is considered at the deuteron energies from 500 up to 2000 MeV. The multiple-scattering-expansion technique is applied to evaluate the reaction amplitude. The one-nucleon-exchange, single scattering and double scattering contributions are taken into account. Also, some relativistic effects are included into consideration. The obtained results are compared with the experimental data both for the differential cross section and polarization observables.