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Cross sections and analyzing powers for the B-11((p) over right arrow ,p(')) reaction have been measured using a 150-MeV polarized proton beam from the AGOR cyclotron at KVI. For the stronger inelastic transitions, also spin-flip probabilities have been extracted. To predict cross sections and spin observables a microscopic (coordinate space) model of elastic scattering has been used, whereas for inelastic scattering calculations were performed in the distorted-wave approximation. In the model calculations a medium-modified two-nucleon effective interaction was used and nuclear structure information was obtained from shell-model calculations in a complete (0+2)(h) over bar omega model space for parity-conserving transitions and a 1 (h) over bar omega shell-model description in the case of parity-changing transitions. With the help of these model calculations, spin-isovector parts of the M1 strengths for the negative-parity states at excitation energies of 2.125 MeV (J(pi)=1/2(-)), 4.445 MeV (J(pi)=5/2(-)), 5.020 MeV (J(pi)=3/2(-)), and 8.920 MeV (J(pi)=5/2(-)) have been extracted and compared to known Gamow-Teller strengths for the analog transitions to C-11.

The polarization-transfer coefficient D-nn(') in the elastic scattering of 150-MeV protons from B-11 has been measured in the angular range 5degrees

The Mg-24(d,He-2)Na-24 and the C-12(d,He-2)B-12 charge-exchange reactions have been studied at an incident energy of 170 MeV. The two protons in the S-1(0)(pp) state (indicated as He-2) were both momentum analyzed and detected by the same spectrometer and detector. Background-free He-2 spectra with a resolution of about 150 keV (full width at half maximum) have been obtained allowing identification of many levels in the residual nucleus with high precision. It is found that the (d,He-2) reaction at 0degrees is largely governed by the Gamow-Teller (GT) transition operator for the beta(+) direction, which makes the reaction selective for isovector 1(+) transitions. In the case of Mg-24, the reaction is compared with (p,n) reaction data in which the same levels in the analog nucleus Al-24 are populated. Angular distributions of cross sections for the (d,He-2) reaction are presented and compared with distorted-wave Born approximation calculations. GT matrix elements are deduced. A level-by-level comparison with shell-model calculations using the universal s-d interaction has been performed. Comparison with (p,p(')) data yields a level scheme for the A=24 isospin triplet.

A series of measurements have been performed at KVI to obtain the vector analyzing power Ay Of the H-2((p) over right arrow, 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 upsilon (c.m) from 30 degrees to 170 degrees 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 degrees and 130 degrees. 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.

Angular distributions for elastic and inelastic deuteron scattering on C-12. Mg-24, and Ni-58 have been measured at a bombarding energy of 170 MeV. The data are analyzed in terms of the optical model. The extracted optical model parameters are compared to existing deuteron global optical potentials.

Angular distributions for elastic and inelastic deuteron scattering on C-12. Mg-24, and Ni-58 have been measured at a bombarding energy of 170 MeV. The data are analyzed in terms of the optical model. The extracted optical model parameters are compared to existing deuteron global optical potentials.

For the medium-energy proton polarimeter mounted at the focal-plane of the Big-Bite Spectrometer at Kernfysisch Versneller Instituut Groningen, a new wire-chamber readout has been developed. The charge-sensitive preamplifier is based on the ASD-8 B chip which has an input impedance of 115 Omega. This low impedance and the short integration time of 6 ns at a usable sensitivity of 5 fC allow high readout rates and low gas amplifications. This front-end circuit is mounted on all four multi-wire proportional chambers and on two vertical-drift chambers with 3872 wires in total. Measurements have been made using sources and intermediate energy protons. Special attention was given to determine the time-over-threshold properties of the circuit, The time-over-threshold capabilities of the readout system extend future applications to particle discrimination, or, in connection with other detector types, to energy-resolving readout, The operational performance of the readout system is presented.

A Focal-Plane Polarimeter (FPP) for the large acceptance Big-Bite Spectrometer (BBS) at AGOR using a novel readout architecture has been commissioned at the KVI Groningen. The instrument is optimized for medium-energy polarized proton scattering near or at 0 degrees. For the handling of the high counting rates at extreme forward angles and for the suppression of small-angle scattering in the graphite analyzer, a high-performance data processing DSP system connecting to the LeCroy FERA and PCOS ECL bus architecture has been made operational and tested successfully. Details of the system and the functions of the various electronic components are described. (C) 1999 Elsevier Science B.V. All rights reserved.

The Focal-Plane Polarimeter (FPP) for the Big-Bite Spectrometer van den Berg (Nucl Instr. and Meth. B 99 (1995) 637ff) at the KVI requires the read-out of four large-area MWPCs and two VDCs with 3872 wires in-total. The EUROSUPERNOVA collaboration (SNOVA) developed a digital 16 channel preamplifier front-end board, housing two amplifier-shaper-discriminatorchips ASD-8 B. The main features of this board are a fast single-wire readout, a high integration density, a low power consumption and compatibility to common instrumentation standards;The board represents the first successfully running application of the ASD-8 for wire chamber readout. (C) 1999 Elsevier Science B.V. All rights reserved.