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We report on a determination of the analyzing power A y in the p → p → p p ω reaction studied with the TOF spectrometer located at the COSY-accelerator (Forschungszentrum Julich, Germany). This spectrometer is very well suited for polarization measurements due to its rotational symmetry and full coverage of the azimuthal angle. For a beam momentum of p = 3065 MeV / c corresponding to an excess energy of ϵ = 129 MeV A y is found to be compatible with zero.

In view of the persisting misunderstandings about the determination of the pion-nucleon coupling constants in the Nijmegen multienergy partial-wave analyses of pp, np, and ppBAR scattering data, we present additional information which may clarify several points of discussion. We comment on several recent papers addressing the issue of the pion-nucleon coupling constant and criticizing the Nijmegen analyses.

The vector and tensor polarizations of a deuteron beam have been measured using elastic deuteron-carbon scattering at 75.6 MeV and deuteron-proton scattering at 270 MeV. After acceleration to 1170 MeV inside the COSY ring, the polarizations of the deuterons were checked by studying a variety of nuclear reactions using a cluster target at the ANKE magnet spectrometer placed at an internal target position of the storage ring. All these measurements were consistent with the absence of depolarization during acceleration and provide a number of secondary standards that can be used in subsequent experiments at the facility., Comment: 12 pages, 13 figures

The model of microscopic optical potential based on calculations of the one-particle Green function mass operator using the effective Skyrme nucleon-nucleon forces has been applied for describing cross sections and analyzing powers of the elastic nucleon-nucleus scattering. The Skyrme force parameters have been optimized by fitting a chosen angular distribution of the elastic neutron-nucleus scattering with simultaneous control of main characteristics of the nuclear matter and the binding energy and rms charge radius of the target nucleus. The found Skyrme forces have been used to analyze differential cross sections and analyzing powers of elastic neutron scattering by nuclei in a wide range of mass numbers. The calculations have given a satisfactory description of experimental data on elastic neutron-nucleus scattering and reasonable values of the main parameters for the symmetric nuclear matter and even-even nuclei. Analogous calculations have been performed for describing experimental data on the elastic proton-nucleus scattering, which have yielded encouraging results.

High-precision measurements of the proton-deuteron elastic and break-up reaction have been performed in the past at KVI and elsewhere with the aim to study three-nucleon force (3NF) effects. In the present work, we explored 3NF effects in the break-up scattering process by performing a measurement of vector analyzing powers and differential cross sections using a 135 MeV polarized-proton beam impinging on a liquid-deuterium target. For this study, we used a new experimental setup, Big Instrument for Nuclear-polarization Analysis, BINA, which covers almost the entire kinematical phase space of the break-up reaction. The results are interpreted with the help of state-of-the-art Faddeev calculations.