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Total and differential cross sections for the reactions p + d→ 3He + m0with m=π, ηand p + d→ 3H+π+were measured with the GEM detector at COSY for beam momenta between threshold and the maximum of the corresponding baryon resonance. For both reactions a strong forward-backward asymmetry was found. The data were compared with model calculations. The aspect of isospin symmetry breaking is studied.

Collective excitations in the two-particle nucleus148Gd up to 2.9 MeV have been investigated by thepp'-reaction at 25 MeV beam energy, and angular distributions have been analyzed with standard DWBA calculations. It is found that148Gd has larger octupole- than quadrupole collectivity in the energy range investigated. The 3- strength distribution is in quantitative agreement with predicted results for the levels formed by the coupling of two valence particles to the146Gd core octupole phonon.

The12C+n total cross section has been studied in the region of the lowestT=3/2 states of13C. The firstT=3/2 state at (15108.2±1.2) keV excitation is observed as a weak resonance anomaly. The deduced resonance parameters agree with previous results. At higher excitation energies four sharp anomalies have been observed at (17534±3) keV, (18082±3) keV, (20057±4) keV and (21703±4) keV excitation with total widths between 12 keV and 20 keV. The results are discussed with respect to a possibleT=3/2 assignment. An upper limit of the elasticity (J+1/2) Gno/gG is deduced for thoseT=3/2 levels which do not appear as resonance anomalies.

Angular distributions of the12C(d,7Li)7Be reaction to the ground and to the unresolved first excited states of7Li or7Be nuclei were measured in the entire angular region in the centre of mass system atElab=78.0 MeV. Both the one-step five-nucleon cluster transfer as well as two-step sequential transfers were considered in the theoretical analysis. The former mechanism was found to dominate, but the latter is also not negligible.

Experimental evidence is presented that the144Nd(p, a)141Pr reaction excites residual nucleus levels with a dominant single proton configuration, suggesting a contribution from knock-on mechanism.

Angular distributions of the10B(a,7Li)7Be reaction were measured atElab = 91.8 MeV in the entire center of mass angular region. A DWBA analysis explains the reaction as triton and helion transfer in the forward and backward angular regions, respectively.

Angular distributions of cross sections have been measured for single nucleon transfer reactions induced by 344.5 MeV12C ions on a12C target. DWBA analyses have been performed for transitions to discrete final states. Spectroscopic information has been derived and is compared with results of other studies.

A high resolution experiment, using the BIG KARL spectrometer has been made to identify the levels of141Pr excited in the144Nd(p,a) reaction at 25 MeV. It has been found that only levels with a dominant single proton component are populated with appreciable intensity.

The reaction pp → K+ + (Λp) has been measured at Tp = 1.953 GeV and Θ = 0° with a high missing-mass resolution in order to study the Λp final state interaction. Narrow S = -1 resonances predicted by bag model calculations are not visible in the missing-mass spectrum. Small structures observed in a previous experiment are not confirmed. Upper limits for the production cross section of a narrow resonance are deduced for missing masses between 2058 and 2105 MeV. [ABSTRACT FROM AUTHOR]