First -and -spectroscopic decay studies of the N 82 r-process ''waiting-point'' nuclide 130 Cd have been performed at CERN/ISOLDE using the highest achievable isotopic selectivity. Several nuclear-physics surprises have been discovered. The first one is the unanticipatedly high energy of 2.12 MeV for the [g 9=2 g 7=2 1 level in 130 In, which is fed by the main Gamow-Teller transition. The second surprise is the rather high Q value of 8.34 MeV, which is in agreement only with recent mass models that include the phenomenon of N 82 shell quenching. Possible implications of these new results on the formation of the A ' 130 r-process abundance peak are presented.

No abstract

No abstract

The N = 28 shell closure has been investigated via the 46Ar(d,p)47Ar transfer reaction in inverse kinematics. Energies and spectroscopic factors of the neutron p(3/2), p(1/2), and f(5/2) states in 47Ar were determined and compared to those of the 49Ca isotone. We deduced a reduction of the N = 28 gap by 330(90) keV and spin-orbit weakenings of approximately 10(2) and 45(10)% for the f and p states, respectively. Such large variations for the f and p spin-orbit splittings could be accounted for by the proton-neutron tensor force and by the density dependence of the spin-orbit interaction, respectively. This contrasts with the picture of the spin-orbit interaction as a surface term only.

No abstract