Level structures of the very neutron-rich Ce-150,Ce-152 have been studied by measuring the prompt g -rays in the spontaneous fission of Cf-252. The yrast bands have been confirmed and many levels and transitions are newly identified in both nuclei. The side-bands are tentatively assigned with negative parity and octupole band structures with s = +1 in Ce-152,Ce-152 have been proposed. The systematic characteristics of the octupole correlations have been discussed.

High spin levels of the very neutron-rich Ce-152 have been investigated by measuring the prompt. rays in the spontaneous fission of Cf-252. The yrast band is confirmed and a new side-band has been identified. The side-band is tentatively assigned with negative parity and an octupole band structure with s = +1 in Ce-152 has been proposed. Based on the theoretical calculations and systematic comparisons, the characteristics of the octupole correlations have been discussed.

Using new techniques developed for measuring angular correlations with large detector arrays, the g factors of 2(+) states in Xe-140,Xe-142 are measured for the first time by the method of correlation attenuation in randomly oriented magnetic fields. g factors in Ba-146 and Ce-146,Ce-148 are measured to establish the method by comparison with previous values. The results are discussed in terms of IBM-2 and rotation-vibration models.

The multipole mixing ratios of Delta I=1 transitions between levels in rotational bands built on single-particle states in odd neutron nuclei are dependent on the configurations of the states. In particular, the mixing ratio can be used to distinguish between several possible single-particle configurations if interpreted with the particle-axial-rotor model. This work features the first determination of the ground-state configurations of Ru-109,Ru-111. The single-particle structures of the ground states of Zr-101 and Mo-103,Mo-105,Mo-107 as well as excited states in Mo-103,Mo-107 are also investigated, with a new result found in Mo-107.

The hadronization of K{sup 0} particles was measured in semi-inclusive deep inelastic scattering (SIDIS) kinematics for several nuclear targets using the CLAS detector. Multiplicity ratios and Δp{sup 2}{sub T} values were extracted from the data. These results may be compared with similar values for π{sup +} hadronization from CLAS (at the same kinematics) and K{sup +} hadronization from HERMES (at higher energy transfer). The physics goal of these measurements is to understand the space-time evolution as the struck quark becomes a full-blown hadron as it propagates through nuclear matter.

The g-factor of the 4(+) state in Te-134 has been measured for the first time by using a new technique developed for measuring angular correlations with Gammasphere. Also reported is the first measurement of the g-factor of the 15/2(+) state in I-135 and the mixing ratios of several transitions. Furthermore, spins and parities are assigned to several levels in Te-134 and I-135. The g-factor measurements are compared to shell model predictions and good agreement is found between experiment and theory.

From the analysis of gamma-gamma-gamma coincidence data taken with Gammasphere of the prompt gamma rays in the spontaneous fission of Cf-252, the 2(+)-> 0(+) transition in Se-88 was identified for the first time. Also, the 4(+)-> 2(+) and 6(+)-> 4(+) transitions in Se-86 were identified along with four new states above 4(+) in Se-84. Surprisingly, the 2(+) energy rises in Se-88 compared to Se-86. This increase in energy could arise from the interaction of a low-lying excited 0(+) state with different deformation and the 0(+) ground state to depress the ground-state energy.

. By using different time-gated triple γ coincidence data, the half-lives ( T 1/2 ) of several short lived states in neutron-rich nuclei have been studied. The first excited states in the ground state bands often decay by delayed γ emission. By creating triple γ coincidence spectra with time windows of 8, 16, 20, 28, and 48 ns, we have studied states with half-lives below 10 ns. The estimated half-lives of 102 Zr, 137 Xe, and 143 Ba are in reasonable agreement with previously reported values. We extract the first estimates of the half lives of the 2 + states in 104 Zr and 152 Ce.

. Half-lives ( T 1/2 ) of several states which decay by delayed γ transitions were determined from time-gated triple γ coincidence method. We determined, for the first time, the half-life of 330.6 + x state in 108 Tc and the half-life of 19/2 - state in 133 Te based on the new level schemes. Five half-lives of 95, 97 Sr, 99 Zr, 134 Te and 137 Xe are consistent with the previously reported ones. These results indicate that this new method is useful for measuring the half-lives.

Ternary fission of Cf-252 was studied at Gammasphere with eight DeltaExE particle telescopes. After Doppler correction, the 3368 keV 2(+)-->0(+) transition in Be-10 was found in coincidence with the Be-10 fragments with no evidence for any gamma rays not Doppler shifted for Be-10 with >21 MeV kinetic energy. The ratio of the first 2(+) to ground-state population probabilities was estimated as N(2(+))/N(0(+))=0.160+/-0.025. The angular distribution for 3368 keV gamma rays indicated the spin alignment of excited Be-10 nuclei preferentially is parallel or antiparallel to their momentum.

Analysis of Cf-252 recent spontaneous-fission gamma data from Gammasphere has enabled the discovery of transitions in Ba-139 in coincidence with those of its Molybdenum fission partner. A new level scheme going up to approximate to5 Mev includes 11 new transitions and 10 new levels. We make analogies with the 83-neutron isotone Te-135 and discuss possible configurations in the spherical single-particle shell model. We suggest a band as a possible magnetic rotation band of the type treated by tilted-axis cranking theory.

The yrast band was significantly extended to 14(+) and the gamma band to 5(+) in neutron-rich Pd-118 by measuring the gamma-gamma-gamma coincidences emitted from the spontaneous fission of Cf-252 with Gammasphere. The first band crossing was observed in the yrast band in Pd-118 at a frequency of (h) over bar omega approximate to 0.36 MeV at the starting point of the backbending. which is similar to that found in Pd112-116. The first bandbending in the yrast cascade in Pd-118 is interpreted to be built on a two h(11/2) neutron configuration based on its similarity to the yrast bands in even-even Pd112-116. Our result indicates Pd-118 still maintains a prolate shape. The quasineutron Routhian calculations indicate a lower crossing frequency for the h(11/2) level.

Neutron-rich Pr-147,Pr-149,Pr-151 nuclei, produced in the spontaneous fission of Cf-252, were studied using the Gammasphere array. Possible parity doublets in Pr-147 With N = 88 and pi h(11/2) bands in Pr-149,Pr-151 are proposed. These new data on the level structures of odd Pr isotopes suggest that octupole correlations may also be present in the neutron-rich Pr-147(59)88 nucleus such as those observed in Ce-146(58)88, and also that the h(11/2) bands in the Pr-149,Pr-151 track in energy the yrast bands in Ce-148,Ce-150. The backbending related to the breaking of the neutron i(13/2) pair is observed at (h) over bar omega approximate to 0.27 (MeV) for the proton h(11/2) band of Pr-149.

Neutron-rich {sup 147,149,151}Pr nuclei, produced in the spontaneous fission of {sup 252}Cf, were studied using the Gammasphere array. Possible parity doublets in {sup 147}Pr with N=88 and {pi}h{sub 11/2} bands in {sup 149,151}Pr are proposed. These new data on the level structures of odd Pr isotopes suggest that octupole correlations may also be present in the neutron-rich {sub 59}{sup 147}Pr{sub 88} nucleus such as those observed in {sub 58}{sup 146}Ce{sub 88}, and also that the h{sub 11/2} bands in the {sup 149,151}Pr track in energy the yrast bands in {sup 148,150}Ce. The backbending related to the breaking of the neutron i{sub 13/2} pair is observed at {Dirac_h}{omega}{approx}0.27 (MeV) for the proton h{sub 11/2} band of {sup 149}Pr.

Neutron-rich {sup 147,149,151}Pr nuclei, produced in the spontaneous fission of {sup 252}Cf, were studied using the Gammasphere array. Possible parity doublets in {sup 147}Pr with N=88 and {pi}h{sub 11/2} bands in {sup 149,151}Pr are proposed. These new data on the level structures of odd Pr isotopes suggest that octupole correlations may also be present in the neutron-rich {sub 59}{sup 147}Pr{sub 88} nucleus such as those observed in {sub 58}{sup 146}Ce{sub 88}, and also that the h{sub 11/2} bands in the {sup 149,151}Pr track in energy the yrast bands in {sup 148,150}Ce. The backbending related to the breaking of the neutron i{sub 13/2} pair is observed at {Dirac_h}{omega}{approx}0.27 (MeV) for the proton h{sub 11/2} band of {sup 149}Pr.

High spin states in neutron-rich odd-Z Ba-143,Ba-145 nuclei have been investigated from the study of prompt gamma rays in the spontaneous fission of Cf-252 by using gamma-gamma- and gamma-gamma-gamma- coincidence techniques. Alternating parity bands are identified for the first time in Ba-145 and extended in Ba-143. A new side band, with equal, constant dynamic, and kinetic moments of inertia equal to the rigid body value, as found in superdeformed bands, is discovered in Ba-145. Enhanced E1 transitions between the negative- and positive-parity bands in these nuclei give evidence for strong octupole deformation in Ba-143 and in Ba-145. These collective bands show competition and coexistence between symmetric and asymmetric shapes in Ba-145. Evidence is found for crossing M1 and E1 transitions between the s = +i and s= -i doublers in Ba-143. [S0556-2813(99)50810-8].

Several new high-spin states are observed in the prompt gamma-rays emitted from the neutron-rich, odd-Z La-145,La-147 fragments produced in the spontaneous fission of Cf-252. Alternating parity bands are extended up to spins 41/2 and 43/2 in La-145,La-147, respectively. A new band completes the evidence for two sell: of parity doublets expected for octupole correlations. Eight B(E1)/B(E2) ratios (four new) between two bands in La-145 are all essentially constant and somewhat larger than similar ratios in Ba-143,Ba-144, where stable octupole deformation and/or correlations are reported. The new ratios out of the 31/2(-) levels in both nuclei show a sharp spike compared to other states, presumably from a strong reduction in E2 strengths in this backbending region. In 145La, collective bands show competition and coexistence between symmetric and asymmetric shapes. Band crossings occur in both nuclei around (h) over bar omega approximate to 0.26-0.30 MeV. Their backbends are associated with the alignment of two i(13/2) neutrons according to cranked shell model calculations. [S0556-2813(99)08402-2].

The phenomenon of cold (neutronless) alpha ternary fission in spontaneous fission of Cf-252 was experimentally observed by triple gamma coincidence technique with Gammasphere with 72 gamma-ray detectors. Correlated pairs of Kr-36-Nd-60, Sr-38-Ce-58, Zr-40-Ba-56, Mo-42-Xe-54, Ru-44-Te-52, and Pd-46-Sn-50 were observed to be associated with alpha ternary fission of Cf-252. Yields of cold alpha ternary fission were extracted.[S0556-2813(98)01005-X].

New experiments using an array of high purity germanium detectors and fast liquid scintillation detectors has been performed to observe the radiation emitted from the induced fission of 235U with a beam of thermal neutrons. The experiment was performed at the Argonne National Laboratory Intense Pulsed Neutron Source. Preliminary observations of the data are presented. A nondestructive analysis system for the characterization of DOE spent nuclear fuel based on these new data is presented.