We report the first observation of a double isovector giant dipole state in nuclei (i.e., an isovector giant dipole resonance built on another giant dipole). Two new resonances were observed in (/r + \K~) double charge exchange (at 7^-292 MeV) on nat S at excitation energies of 24.7 and 28.7 MeV. The energy centroid is very close to the energy at which the double dipole C/*= 5 0" , ",2 + ; T-2) state is expected to appear. The angular distributions for the resonances have a clear quadrupole shape. The measured cross sections and the angular distribution agree well with a simple sequential two-step calculation in which single charge exchange through the giant dipole resonance to the double dipole is evaluated.
Low spin states of 22'Th have been populated via a-decay. The parent nucleus ("' U, l,n-1 min) was formed in the reaction zoaPb(22Ne, 3n)'"U. E, , , = 110 MeV. Out-of-beam measurements of a-y and e-e-coincidences were performed with the aid of a rotating target mechanism. These measurements have enabled a limited level scheme of the low-spin states in ' ' ?h to be constructed, along with tentative J' assignments and LI hindrance factors. The data are interpreted in terms of thc geometric model assuming a static octupole deformation and compared to that for the N = 133 isotone$ '"Ra and 'IYRn.
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