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In even-mass Te isotopes with 114 ≤ A ≤ 122 the experimentally observed yrast Iπ = 16+ states have been interpreted as favored noncollective oblate states based on the fully aligned π[(g7/2)²]6+ ⊗ ν[(h11/2)²]10+ configuration. For 124Te the highest-spin positive-parity state known has lπ = 10+. An extension of the yrast cascade of 124Te is needed to spin at least 16+ in order to answer the question of whether this noncollective oblate state lies along the yrast line in this isotope. The level structure of 124Te has been studied via prompt y-ray spectroscopy. 124Te was produced in the fission of the compound systems formed in two heavy-ion-induced reactions, 24Mg (134.5 MeV) + 173Yb and 23Na (129 MeV) + 176Yb. γ-ray spectroscopy was accomplished with the Gammasphere array. The yrast cascade of, 24Te was extended up to 5481-keV excitation energy with a tentative 16+ assignment for the highest observed state. This state does not exhibit the characteristics of the favored noncollective oblate states with Iπ = 16+ observed in the lighter doubly even Te isotopes, indicating that such a state is probably no longer yrast in 124Te. [ABSTRACT FROM AUTHOR]

High-spin states in 120Te were populated in the reaction 80Se(>48Ca,&agr;4n))120Te at a beam energy of 207 MeV and &ggr;-ray coincidences were measured using the Gammasphere spectrometer. The previously known level scheme is extended to higher spin and new interband transitions and side-feeding branches are established. Five highly deformed rotational bands, extending up to almost l = 50, are observed for the first time. The bands are compared with similar structures found recently in neighboring nuclei. The experimental results are interpreted within the framework of the cranked Nilsson-Strutinsky model. Configuration assignments to several terminating states and to the high-spin bands are discussed. [ABSTRACT FROM AUTHOR]

High-spin states have been studied in Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. populated through the 116Cd(23Na,4n) reaction at 115 MeV, using the Gammasphere γ-ray spectrometer. The negative-parity yrast band has been significantly extended to spin ~45ħ and excitation energy 21.5 MeV, showing evidence for several rotational alignments. The positive-parity yrast band of Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed., populated through the p4n channel of this reaction, was also populated to spin ~38ħ and excitation energy 18 MeV. Cranking calculations indicate that these nuclei are soft with respect to the triaxiality parameter γ and that several competing nuclear shapes occur at high spin. [ABSTRACT FROM AUTHOR]

The 31Si nucleus was produced through the 18O(18O, αn) fusion-evaporation reaction at Elab=24MeV. Evaporated α particles from the reaction were detected and identified in the Microball detector array for channel selection. Multiple γ-ray coincidence events were detected in Gammasphere. The energy and angle information for the α particles was used to determine the 31Si recoil kinematics on an event-by-event basis for a more accurate Doppler correction. A total of 22 new states and 52 new γ transitions were observed, including 14 from states above the neutron separation energy. The positive-parity states predicted by the shell-model calculations in the sd model space agree well with experiment. The negative-parity states were compared with shell-model calculations in the psdpf model space with some variations in the N=20 shell gap. The best agreement was found with a shell gap intermediate between that originally used for A≈20 nuclei and that previously adapted for 32,34P. This variation suggests the need for a more universal cross-shell interaction. [ABSTRACT FROM AUTHOR]