The evaporation-residue counter HERCULES, an auxiliary detector for GAMMASPHERE to perform spectroscopy in the presence of a large fission background, is described. Results from a typical experiment using the 26Mg + 198Pt → 224Th* reaction at 128 MeV are discussed. The discussion focuses on the new 220Th level scheme. The simplex feature (alternating-parity levels) persists up to the highest spins observed. However, 220Th exhibits a more vibrational-like behavior than the heavier Th isotopes. A novel interpretation for 220Th based on a picture of tidal waves on a reflection- asymmetric nuclear surface is briefly reviewed. Finally, the identification of excited states in 219Th is discussed.
|Number of pages||9|
|Journal||Acta Physica Polonica B|
|State||Published - Apr 1 2007|
|Event||41st Zakopane Conference on Nuclear Physics - Trends in Nuclear Physics - Zakopane, Poland|
Duration: Sep 4 2006 → Sep 10 2006