Search for Three-Nucleon Force Effects in Analyzing Powers for p→d Elastic Scattering

A series of measurements have been performed at KVI to obtain the vector analyzing power Ay of the 2H(p→,pd) reaction as a function of incident beam energy at energies of 120, 135, 150, and 170 MeV. For all these measurements, a range of ϑc.m. from 30° to 170° has been covered. The purpose of these investigations is to observe possible spin-dependent effects beyond two-nucleon forces. When compared to the predictions of Faddeev calculations, based on two-nucleon forces only, significant deviations are observed at all energies and at center-of-mass angles between 70° and 130°. The addition of present-day three-nucleon forces does not improve the description of the data, demonstrating the still insufficient understanding of the properties of three-nucleon systems

Search for isovector giant monopole resonances via the Pb(He-3,tp)reaction

The Pb-nat(He-3, tp) reaction at E(He-3) = 177 MeV was studied to identify 2hw isovector monopole strength in Bi isotopes. Monopole strength was found in the region -45 < Q < -30 MeV in the coincidence data. The cross section is compared with distorted-wave Born approximation calculations for non-spin-flip and spin-flip isovector monopole resonances. The observed spin-flip and non-spin-flip monopole strengths in the proton-decay channel amount to 20% of the respective non-energy-weighted sum rule

Performance of the KVI in-beam polarimeter

A beam polarimeter for medium-energy protons and deuterons has been constructed. Its operation is based on the elastic-scattering reactions (p) over right arrow + p or (d) over right arrow + p. The outgoing particles are detected in kinematical coincidence in four independent reaction planes, each equipped with two pairs of phoswich detectors. (C) 2001 Published by Elsevier Science B.V