An experiment was performed with the EUROGAM II array to investigate the reaction channels that are open in the fusion of a beam on the actinide target at a series of energies around the Coulomb barrier. The symmetric fission products identified from the level structures seem to suggest that a proton and neutrons are emitted prior to fission.

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High-spin states of 89 Sr and 90 Sr were studied via the reactions 82 Se( 11 B, p3n) and 82 Se( 11 B, p2n), respectively, at a beam energy of 37 MeV. Gamma rays were detected with the GASP spectrometer. The level schemes of 89 Sr and 90 Sr were extended up to EϷ8 MeV and EϷ10 MeV, respectively. Level structures in 89 Sr and 90 Sr were interpreted in terms of the spherical shell model. The calculations were performed in the configuration space (0 f 5/2 ,1p 3/2 ,1p 1/2 ,0g 9/2 ) for the protons and (1p 1/2 ,0g 9/2 ,1d 5/2 ) for the neutrons. Highspin level sequences in 89 Sr are characterized by coupling the unpaired d 5/2 neutron to proton excitations of the core nucleus 88 Sr. An equidistant level sequence with ⌬Jϭ2 found in 90 Sr is well described by the configuration ͓(0 f 5/2Ϫ2 )(0g 9/2 2 )͔(1d 5/2 2 ) favoring even spins.

A stack of annular detectors made of high purity germanium was used to measure simultaneously pd → 3 H π + and pd → 3 He π 0 differential cross sections at beam momenta of 750 MeV/c, 800 MeV/c, and 850 MeV/c over a large angular range. The extracted total cross sections for the pd → 3 He π 0 reactions bridge a gap between near threshold data and those in the resonance region. The ratio of the cross sections for the two reaction channels taken at the same η = p cm π /m π yields 2.11±0.08 indicating that a deviation from isospin symmetry is very small.