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Abstract: We report on the first in-beam γ-ray spectroscopy of 23Al using two different reactions at intermediate beam energies: inelastic scattering off 9Be and heavy-ion induced one-proton pickup, 9Be(22Mg,23Al+γ)X, at 75.1 MeV/nucleon. A γ-ray transition at 1616(8) keV—exceeding the proton separation energy by 1494 keV—was observed in both reactions. From shell model and proton decay calculations we argue that this γ-ray decay proceeds from the core-excited state to the ground state of 23Al. The proposed nature of this state, [22Mg, is consistent with the presence of a γ-branch and with the population of this state in the two reactions. [Copyright &y& Elsevier]

Abstract: The ground-state structure of the near-drip-line nucleus 23O has been investigated in a one-neutron Coulomb breakup reaction. Differential cross sections for electromagnetic excitation of 23O projectiles (422 MeV/nucleon) incident on a lead target have been obtained from the measurement of the momenta of all breakup products including γ rays. The analysis of the deduced dipole-transition probability into the continuum infers a ground state configuration with a spectroscopic factor of 0.77(10) and thus a ground-state spin , resolving earlier conflicting experimental findings. Final-state interaction is of significant influence, an effective reduced scattering length for low-energy neutron scattering could be derived from the data. [Copyright &y& Elsevier]