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We identified &b.gamma; transitions in several neutron-rich nuclei near [SUP132]Sn produced in the spontaneous fission of [SUP252]Cf. These are of interest because they can test shell model calculations. These nuclei are [SUP139]Ba, [SUP133,135]Te, and [SUP121,123]Cd. Excited states in neutron-rich [SUP133]Te exhibit four types of particle-hole bands built on the known 334.3 keV isomer in [SUP133]Te. The yrast and near yrast particle-hole states observed up to 6.2 MeV in [SUP133]Te have characteristics quite similar to those in [SUP134]Te. The band starting at 5.214 MeV is assigned as a neutron particle-hole excitation of the double magic core nucleus, [SUP132]Sn and is a candidate for a tilted rotor band. Theoretical shell model calculations show good agreement with the experimental states up to 4.3 MeV. The new level scheme of [SUP139]Ba includes 11 new transitions and 10 new levels and is compared with the 83-neutron isotone [SUP135]Te. In [SUP135]Te, a tilted rotor band, also, is proposed. Excited states built on the 11/2[SUP-] isomeric states in neutron-rich [SUP121,123]Cd are identified. The new data indicate that the 11/2[SUP-] isomers in odd-A Cd isotopes with N>74 have spherical shapes similar to those in Te while the Cd ground states are likely deformed. [ABSTRACT FROM AUTHOR]

New analyses of spontaneous-fission gamma data from our [sup 252]Cf Gammasphere runs of 1995 and 2000 have identified new transitions and given improved transition energy and intensity values for known transitions in even-odd fission-product nuclei just beyond the 82-neutron closed shell. New level schemes of N=83 isotones [sup 139]Ba[sub 83] and [sup 135]Te[sub 83] and of N=85 isotones [sup 141]Ba[sub 85], and [sup 139]Xe[sub 85] are established. Single-particle (hole) excitations and couplings, core excitations, and octupole excitations are assigned to these isotones. A regular sequence found in [sup 135]Te is interpreted as a shears band within the tilted-axis cranking model of Frauendorf. The level systematics of N=85 isotones indicate that the octupole excitation moves to higher excitation energy as the Z=50 shell is approached. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The Berkeley Gas-filled Separator provides new research opportunities at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. The use of this apparatus for the study of proton drip-line nuclides is discussed. Preliminary results of [sup78]Kr bombardments of [sup102]Pd targets at mid-target energies of 360, 375 and 385 MeV are presented. Improvements planned partially as a result of this measurement are also discussed [ABSTRACT FROM AUTHOR]