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Measurements of deexcitation g rays in coincidence with the momentum distribution of the projectile residues produced in reactions of the type 9 Be͑ 28 P, 27 Si 1 g͒X at energies around 65 MeV͞u are used to study single-nucleon stripping to individual states. The cross sections are compared with calculations based on an eikonal model description of the reaction and the shell model. The measurements indicate that the halo character of the ground state and other detailed spectroscopic information can be derived using knockout reactions in inverse kinematics. [S0031-9007(98)

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A high-resolution study of dipole transitions to bound states up to 10 MeV in the f p-shell nuclei 56 Fe and 58 Ni was performed by means of the nuclear resonance fluorescence method. Unpolarized and partially linearly polarized bremsstrahlung photons with different end point energies ͑6.5, 10, and 12 MeV͒ were used to determine excitation energies, spins, parities, and transition widths of more than 60 levels observed in each nucleus between 2 and 10 MeV. The vast majority of the observed transitions are dipole ones and to the strongest of them an E1 assignment could be given. The E1 strength distribution shows a high concentration around 8.2 MeV that may be connected with the E1 pygmy resonance in heavier nuclei. The M 1 spin-flip strength shows a concentration around 8.7 MeV in 58 Ni. On the contrary, in 56 Fe its distribution is rather flat. The observed M 1 strength is weak in both nuclei. A study was made of the feeding and branching of the observed levels. Calculations were performed for these nuclei in the framework of the quasiparticle phonon model and a comparison with experimental results is made. Apart from the strength, experimental and calculated results agree quite well and information about a scissorslike mode in 56 Fe and a 1 Ϫ two-phonon state in 58 Ni could be extracted.

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