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5 pags. ; 3 figs. ; PACS numbers: 23.40.-s, 21.10.Pc, 27.60.+j, 21.60.Cs ; Taprogge, J., et al.

A superdeformed rotational band has been identified in ${}^{36}\mathrm{Ar}$, linked to known low-spin states, and observed to its high-spin termination at ${I}^{\ensuremath{\pi}}{\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}16}^{+}$. Cranked Nilsson-Strutinsky and spherical shell model calculations assign the band to a configuration in which four $\mathrm{pf}$-shell orbitals are occupied, leading to a low-spin deformation ${\ensuremath{\beta}}_{2}\ensuremath{\approx}0.45$. Two major shells are active for both protons and neutrons, yet the valence space remains small enough to be confronted with the shell model. This band thus provides an ideal case to study the microscopic structure of collective rotational motion.

Excited states in Ta-180 have been identified using the Yb-176(B-11,alpha 3n)Ta-180 and Yb-176(Li-7,3n)Ta-180 reactions and associated time-correlated gamma-ray spectroscopy, including particle-gamma coincidences for channel selection. As well as identifying the rotational band based on the 9(-) two-quasiparticle state at 75 keV, at least eight other low-lying two-quasiparticle states and associated rotational bands have been established. Lifetimes in the few nanosecond region were isolated using gamma-gamma-time techniques. Most of the observed two-quasiparticle states and some of the band members can be identified with states known from particle transfer studies. The properties of the observed Omega(n)+/-Omega(p) partners of 1(+) and 8(+) bands from the nu 9/2(+)[624]circle times pi 7/2(+)[404] configuration and the 0(-) and 9(-) pair from the nu 9/2(+)[624]circle times pi 9/2(-)[514] configuration are discussed. High-K structures identified include the band based on the four-quasiparticle 45 mu s, 15(-) isomer, a 32 ns, four-quasiparticle 18((+)) isomer, and a six-quasiparticle 19((-)) intrinsic state and its band. Configuration assignments are aided by analysis of the in-band decay properties, which confirm, for example, a predominantly nu pi(3) configuration for the 15- isomer. The results are compared with multiquasiparticle calculations. A number of yrast high-K six- and eight-quasiparticle states which could be accessible in future studies are predicted.

Excited states in {sup 108}Te have been identified up to spins of {approximately}20{h_bar} using the extremely weak 2p2n evaporation channel ({approximately}0.2{percent} of {sigma}{sub fus}) from the bombardment of a backed {sup 54}Fe target with 243 MeV {sup 58}Ni ions. Channel selection and enhancement was made possible using the power of the GAMMASPHERE array to measure high-fold {gamma}-ray coincidences and the resultant application of multiple {gamma}-ray gating techniques. The observation in {sup 108}Te of two interleaved sequences of levels with assumed opposite parity connected by enhanced E1 transitions is interpreted in terms of octupole correlations. The current results for {sup 108}Te make it the closest nucleus to the predicted region of octupole deformation centered at N=Z=56 yet studied to high spin. {copyright} {ital 1998} {ital The American Physical Society}

Deep-inelastic collisions of a 208Pb beam on a 208Pb target were performed using the ATLAS accelerator at Argonne National Laboratory. The Gammasphere detector array was used for the detection of prompt and delayed gamma-rays of the reaction products.207Tl is one proton away from the 208Pb doubly-magic nucleus. Its low-energy level structure is dominated by the single proton-hole states πs1/2−1, πd3/2−1 and πh11/2−1. The 11/2− state is isomeric with T1/2 = 1.33(11) s. The reaction partner of 207Tl is 209Bi, which has arelatively well established level scheme compared to 207Tl. Cross-coincidences between these two nuclei were used to confirm or establish levels above the 11/2− isomeric state in 207Tl. These states are obtained via breaking of the neutron core. Angular correlation analysis was performed on known transitions in 208Pb, proving the applicability of this method for multipolarity assignment.

The level structures of the very neutron-rich nuclei $^{128}\mathrm{Pd}$ and $^{126}\mathrm{Pd}$ have been investigated for the first time. In the $r$-process waiting-point nucleus $^{128}\mathrm{Pd}$, a new isomer with a half-life of $5.8(8)\text{ }\text{ }\ensuremath{\mu}\mathrm{s}$ is proposed to have a spin and parity of ${8}^{+}$ and is associated with a maximally aligned configuration arising from the ${g}_{9/2}$ proton subshell with seniority $\ensuremath{\upsilon}=2$. For $^{126}\mathrm{Pd}$, two new isomers have been identified with half-lives of 0.33(4) and $0.44(3)\text{ }\text{ }\ensuremath{\mu}\mathrm{s}$. The yrast ${2}^{+}$ energy is much higher in $^{128}\mathrm{Pd}$ than in $^{126}\mathrm{Pd}$, while the level sequence below the ${8}^{+}$ isomer in $^{128}\mathrm{Pd}$ is similar to that in the $N=82$ isotone $^{130}\mathrm{Cd}$. The electric quadrupole transition that depopulates the ${8}^{+}$ isomer in $^{128}\mathrm{Pd}$ is more hindered than the corresponding transition in $^{130}\mathrm{Cd}$, as expected in the seniority scheme for a semimagic, spherical nucleus. These experimental findings indicate that the shell closure at the neutron number $N=82$ is fairly robust in the neutron-rich Pd isotopes.

${}^{116}\mathrm{Ru}$ and ${}^{118}\mathrm{Ru}$ have been studied via $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$-ray spectroscopy of nuclei produced in fragmentation reactions at the Radioactive Ion-Beam Factory (RIBF) facility. Level schemes with positive-parity states up to spin $J=6$ have been constructed. The results have been discussed in terms of the interacting boson model, the algebraic collective model, and total Routhian surfaces. We conclude that the very neutron-rich nuclei still show many features associated with triaxial $\ensuremath{\gamma}$-soft nuclei, represented by the O(6) symmetry, but are approaching a spherical structure, the U(5) symmetry, with increasing neutron number towards the $N=82$ shell closure. In ${}^{118}\text{Ru}$, hints of a shape transition in the ground state have been observed.

A six-quasiparticle isomer with ${K}^{\ensuremath{\pi}}={21}^{\ensuremath{-}}$, a half-life of 290(12) ms, and the ${\ensuremath{\pi}}^{3}{\ensuremath{\nu}}^{3}$ configuration has been identified in the odd-odd nucleus $^{178}\mathrm{Ta}$, at an excitation energy of 2902 keV. The rotational bands built on the known ${K}^{\ensuremath{\pi}}={15}^{\ensuremath{-}}$ isomer and on the newly found ${16}^{+}$ four-quasiparticle and ${22}^{+}$ six-quasiparticle states, have also been identified, allowing characterization of the configurations. The ${15}^{\ensuremath{-}}$ band is predominantly of $\ensuremath{\pi}{\ensuremath{\nu}}^{3}$ character with a ${\ensuremath{\pi}}^{3}\ensuremath{\nu}$ admixture. When the mixing is taken into account the excitation energies of the main yrast multi-quasiparticle states can be reproduced. The multi-quasiparticle states observed are related essentially through the addition of the two-quasiparticle component ${\ensuremath{\nu}}^{2}[{6}^{+}]$ or ${\ensuremath{\pi}}^{2}[{6}^{+}]$. Depending on whether the transition between the states involves the change ${\ensuremath{\nu}}^{2}[{6}^{+}]\ensuremath{\rightarrow}[0]$ or ${\ensuremath{\pi}}^{2}[{6}^{+}]\ensuremath{\rightarrow}[0]$, the $E2$ hindrance factors for decays between the six- and four-quasiparticle states are relatively large or small. This dependence mimics the pattern observed in the two-quasiparticle core transitions and, because the ${15}^{\ensuremath{-}}$ isomer is mainly $\ensuremath{\pi}{\ensuremath{\nu}}^{3}$, the magnitude sequence is inverted compared to that observed in $^{176}\mathrm{Ta}$.

High-spin states up to {ital I}{approximately}20{h_bar} have been studied in the {sup 121,122}Te nuclei using the {sup 116}Cd({sup 9}Be,{ital x}n) reaction at 37.8 MeV. In this spin regime, several favored noncollective oblate states ({gamma}=+60{degree}), where the single-particle angular momenta generate the total nuclear spin, are predicted to coexist with weakly deformed collective structures. Theoretical expectations for such oblate states, based on TRS cranking calculations, are compared to the experimental results. {copyright} {ital 1996 The American Physical Society.}

A novel implantation-decay technique has been employed to measure the magnetic moments of the ${2}_{1}^{+}$ states in the neutron-deficient nuclei ${}^{184}\mathrm{Pt}$, ${}^{186}\mathrm{Pt}$, and ${}^{188}\mathrm{Pt}$. The magnetic moment systematics for the even Pt isotopes now extend from ${}_{78}^{184}{\mathrm{Pt}}_{106}$ to ${}_{78}^{198}{\mathrm{Pt}}_{120}$, spanning the upper half of the valence neutron shell. Despite the prolate-to-oblate shape transition near $A\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}190$, they remain remarkably constant. The $g({2}_{1}^{+})$ values for ${}^{184,186,188}\mathrm{Pt}$ are consistent with shape-coexistence models in which the deformed configuration has a larger effective number of valence protons than the less-deformed configuration.

The level structures of the very neutron-rich nuclei 128Pd and 126Pd have been investigated for the first time. In the r-process waiting-point nucleus 128Pd, a new isomer with a half-life of 5.8(8) μs is proposed to have a spin and parity of 8(+) and is associated with a maximally aligned configuration arising from the g(9/2) proton subshell with seniority υ=2. For 126Pd, two new isomers have been identified with half-lives of 0.33(4) and 0.44(3) μs. The yrast 2(+) energy is much higher in 128Pd than in 126Pd, while the level sequence below the 8(+) isomer in 128Pd is similar to that in the N=82 isotone 130Cd. The electric quadrupole transition that depopulates the 8(+) isomer in 128Pd is more hindered than the corresponding transition in 130Cd, as expected in the seniority scheme for a semimagic, spherical nucleus. These experimental findings indicate that the shell closure at the neutron number N=82 is fairly robust in the neutron-rich Pd isotopes.

High spin gamma-ray spectroscopy of 185 Tl and 187 Tl has been performed with the reactions 154 Gd( 35 Cl, 4n) and 159 Tb( 32 S, 4n). Positive γ-ray identification with the thallium isotopes was made via X-ray coincidences, and supported by mass selected γ-ray spectra, the latter obtained with the reactions 154 Gd( 36 Ar, p4n) and 155 Gd( 36 Ar, p3n). Rotational bands associated with both prolate and oblate shape were observed. The bandheads of the proposed oblate 13 2 + [606] states were found to be isomeric, with meanlives of 12 ± 2 ns in 185 Tl and 1.0 ± 0.2 ns in 187 Tl. Prolate deformed i 13 2 bands were observed in both nuclei, while in 187 Tl, bands due to h 9 2 and f 7 2 protons coupled to the prolate shape are also assigned. An h 9 2 band is tentatively assigned in 185 Tl. The observation of these rotation-aligned bands at low excitation energy implies that the development of prolate deformed minima in the odd nuclei is not necessarily blocked by occupation of a single deformation-driving orbital. Equilibrium deformation calculations for intrinsic states in a range of thallium nuclei are presented. Experimental trends with mass number are reproduced, but absolute excitation energies, and energy differences between the prolate and oblate states are not, continuing the persistent discrepancy between theory and experiment in the mercury region. Theoretical calculations of intruder orbital occupation probabilities show a correlation between prolate deformation and h 9 2 and f 7 2 proton pair population, in particular of the 1 2 − [541] orbital from the h 9 2 proton shell. They also show that blocking of the 1 2 − [541] orbital significantly suppresses the prolate deformation. Implications for the structure of the prolate deformed mercury and thallium isotopes are considered, leading to the conclusion that the prolate mercury core nuclei consist of a mixture of low-Ω proton intruder excitations.

Previous studies of 172 Os noted an anomaly in the behaviour of the moment of inertia of the yrast band at low spin. A phenomenological model of shape coexistence based on interacting rotational bands was proposed to explain this anomaly and this model predicted low-lying non-yrast states. In order to test these predictions, the β-decay of 172 Ir has been used to populate 172 Os. Excited states have been observed and classified into positive-parity “quasi-β” and “quasi-γ” bands and a negative-parity band. The energies of the quasi-β band states are seen to be in general agreement with the predictions of the phenomenological model and the model is refined to take into account the new data. The bands involved are determined to have significantly different moments of inertia.

High-spin states of the stable isotope 182W have been studied using the reactions 176Yb(13C, α3n)182W and 176Yb(9Be, 3n)182W at beam energies of 65 and 40 MeV, respectively. Three, possibly four, new intrinsic states at high spins have been observed corresponding to different high-K four-quasi-particle structures. The Kπ = 15+ and 17− levels have lifetimes of 78(15) and 25(10) ns, respectively. Rotational bands are observed built on the Kπ = 16+ and 17− yrast states. The coupling of Nilsson orbitals which give rise to high-K states at the yrast line and the K-forbiddenness of the K π = 15 + isomeric decay are discussed.

Excited states in the odd-odd nucleus 214 Fr have been studied using γ-ray and electron spectroscopy following 208 Pb( 11 B, 5n) and 205 Tl( 13 C, 4n) reactions. Levels were identified to spins of around 36 ħ and excitation energies of ∼ 8.6 MeV. A number of isomeric states have been measured and g -factors obtained using the TDPAD method. At low spin, semi-empirical shell-model calculations appear to provide a good description of the states observed. An understanding of the structure of higher spin states in terms of the probable yrast configurations requires the addition of two units of spin at an energy of around 2 MeV. States with spins around 30 ħ are formed by core-excited configurations, with double core-excitation suggested for the highest states observed. The properties of many of the isomeric states can be understood in terms of multiparticle octupole coupling, with the properties of these states well reproduced by multiparticle octupole-coupled shell-model calculations.

High-spin states of the N=57 isotones, 103Pd and 105Cd, have been studied using the reactions 94Zr(16O, alpha 3n)103Pd and 94Zr(16O,5n)105Cd. The nu h11/2 yrast bands in both nuclei are extended up to spin 47/2h(cross), past the first band-crossing. The observed increase in alignment in both bands is significantly lower than in analogous bands in the heavier odd-N isotopes, where the alignment is thought to be due to a pair of low- Omega h11/2 neutrons. The relatively low increase in alignment in 103Pd and 105Cd is consistent with cranked shell model calculations which predict that at low deformation both the (g9/2)2 proton and the (g7/2)2 neutron alignments are favoured in these N=57 isotones, over the (h11/2)2 neutron alignment.

Transient-field precessions were measured following projectile Coulomb excitation of 24 Mg(2 1 + ). We conclude that (i) the transient field for Mg in Fe decreases markedly with increasing Mg velocities above 7ν 0 due to a diminished efficiency for transfer of polarization to the moving ion, and (ii) the present results contradict earlier evidence for momentary losses in ferromagnetism purported to occur when heavy beams are used for excitation.

A Fermi-aligned ( i 13 2 ) 2 rotational band, with K≈8, has been observed in an even-even nucleus, 180W. Its structure corresponds to a t-band in the tilted-cranking representation. It crosses the ground-state band at I = 16 h , giving rise to backbending in the yrast sequence. Contrary to the usual interpretation, backbending in this case is not caused by the s-band. Comparison is made with other possible t-band crossings in the A ≈ 180 region.

High spin states have been observed to excitation energies over 8 MeV in the odd-odd nucleus 214 Fr using in-beam γ-ray and electron spectroscopic techniques and heavy-ion induced reactions. Semi-empirical shell model calculations appear to provide a good description of the states observed, although some states expected within this model have yet to be identified.

Excited states in the N = 126 nucleus 214Ra have been studied using γ-ray and electron spectroscopy following reactions of 12C and 13C on 206Pb targets. Levels were identified to spins of ∼ 25 ħ and excitation energies of ∼ 7.8 MeV. Lifetimes and magnetic moments were measured for several levels, including a spin (25−) core-excited isomer at 6577.0 keV with τ = 184 ± 5 ns and g = 0.66 ± 0.01. The level scheme, lifetime and magnetic moment data are compared with, and discussed in terms of, empirical shell-model calculations and multiparticle octupole-coupled shell-model calculations. In general, the experimental data are well described by the empirical shell model.

This work was supported by the ANSTO program for Access to Major Research Facilities, grant No. 02/03-H-05, the Australian Research Council Discovery projects DP0343027 and DP0345844, and the U.S. Department of Energy, Office of Nuclear Physics, under contract No. DE-AC02-06CH11257 and No. DE-FG02-94ER40848. P.N. acknowledges funding from the Academy of Finland (Grant 121110).

β -decay spectroscopy of nuclei far from stability can provide powerful insight into a broad variety of topics in nuclear science, ranging from exotic nuclear structure phenomena, stellar nucleosynthesis processes, and applied topics such as quantifying “decay heat” discrepancies for advanced nuclear fuel cycles. Neutronrich nuclei approaching the drip-line are difficult to access experimentally, leaving many key examples largely under studied. The CARIBU radioactive beam facility at Argonne National Laboratory exploits spontaneous fission of 252 Cf in production of such beams. The X-Array and SATURN decay station have been commissioned to perform detailed decay spectroscopy of low-energy CARIBU beams. An extended science campaign was started during 2015; with projects investigating nuclear shape changes, collective octupole vibrations, β -delayed neutron emission, and decay-scheme properties which could explain the reactor antineutrino puzzle. In this article we review the current status of the setup, update on the first results and recent hardware upgrades, and look forward to future possibilities.

Rotational bands built on one- and three-quasiparticle states in 175 Ta have been populated through the 170 Er( 10 B,5n) reaction. The four previously known one-quasiproton bands based on intrinsic states arising from g 7 2 , d 5 2 , h 9 2 and h 11 2 parents were extended to higher spin. Two new three-quasiparticle states with K π = 17 2 + and 21 2 + and their rotational bands were established, as was the rotational band associated with the previously known K π = 21 2 − three-quasiparticle state at 1565.9 keV. B( M 1) B( E 2) and g K − g R values extracted from the in-band branching ratios, have been utilized, together with the decay properties and alignments, to assign configurations. A multi-quasiparticle calculation based on the Lipkin-Nogami method, including approximately the orbital-dependent residual nucleon-nucleon interactions, has been used to predict the multi-quasiparticle energies for comparison with experiment.

Independent yields of post-neutron emission, secondary fragments from the fission of 238U induced by fast neutrons have been measured using γ-γ coincidence data. The yields of these products are found to be centred on more neutron-rich isotopes than the yields from fission processes previously used for spectroscopic studies on neutron-rich nuclei. The average angular momentum in the fragments is found to be similar to that in fragments formed in other low-energy fission processes.

A K(pi)=13+, 280 ns four-quasiparticle isomer in the odd-odd nucleus 174Lu has been identified and characterized. The isomer decays to both K(pi)=7(+) and K(pi)=0(+) rotational bands obtained from the parallel and antiparallel coupling of the proton 7/2+[404] and neutron 7/2+[633] orbitals. K mixing caused by particle-rotation coupling explains the anomalously fast transition rates to the 7+ band but those to the 0+ band are caused by a chance degeneracy between the isomer and a collective state, allowing the mixing matrix element for a large K difference to be deduced.

The E3 decays of the 11- isomers in the isotopes Pb194 and Pb196 have been studied experimentally and evaluated in terms of configuration mixing due to the development of oblate deformation. New results include a remeasurement of the lifetime of the 11- isomer in Pb194 and clarification of the intensities of its main decay branches including the known 496 keV E3 branch. Its intensity is an order of magnitude weaker than previously reported, leading to an E3 transition strength of 29(4) W.u. Limits are placed on possible E3 decays of the 11- isomer in Pb196 to a previously assigned 8+ two-proton state. Neither the branch, nor the state is observed. An alternative 562 keV transition to a new state at 2630 keV is proposed, with an E3 strength of 26(2) W.u. The approximately constant E3 strength for the range of even-even isotopes Pb190-196 is consistent with an oblate deformation for the 11- state of similar magnitude. This is supported by K-constrained potential-energy-surface calculations for the 11- and 8+ configurations.

A beam of 28 MeV He-8 particles with an average intensity 2 x 10(5) ions s(-1), produced by the SPIRAL facility at GANIL, was used to initiate fusion-evaporation reactions in thick targets of Pb-201 and Bi-209. Excited states of Po-212 and At-213 were populated in (He-8,4n) reactions. The emitted gamma-rays were detected using the EXOGAM array composed of four Compton suppressed germanium Clover detectors in a close geometry configuration. Preliminary results show that Po-212 has been populated to high spin (I similar or equal to 14) with a significantly increased yield compared with our previous He-8 beam experiment. An apparently increased relative population of states up to 12(+) was observed compared with published results from a Pb-208(Be-9,alpha n)(212) Po reaction at 48 MeV. Evidence is presented for a previously unreported de-excitation pathway: 69 keV (13(-) -> 12(+)). States up to I-pi = (39/2(-)) have also been observed in At-213.

High-angular-momentum states in Zn-64 were populated in the Ca-40(Si-28,4p) reaction at a beam energy of 122 MeV. Evaporated, light, charged particles were identified by the Microball, while gamma rays were detected using the Gammasphere array. The main focus of this paper is on two strongly coupled, collective bands. The yrast band, which was previously known, has been linked to lower-lying states establishing the excitation energies and angular momenta of in-band states for the first time. The newly identified excited band decays to the yrast band but firm angular-momentum assignments could not be made. In order to interpret these structures cranked-Nilsson-Strutinsky calculations have been performed. The calculations have been extended to account for the distribution of nucleons within a configuration. The yrast collective band is interpreted as based on the pi(f(7/2))(-1)(p(3/2)f(5/2))(2)(g(9/2))(1)nu(p(3/2)f(5/2))(4)(g(9/2))(2) configuration. There are several possible interpretations of the second band but it is difficult to distinguish between the different possibilities.

The excitation energy, spin and parity of the yrast superdeformed (SD) band in 152Dy have been established. The excitation energy of the lowest observed level in this band is found to be 10,644 keV with an assigned spin and parity of 24+. In addition, nine transitions of dipole character have been identified, which connect the excited superdeformed band 6 in 152Dy to the yrast SD band. The excitation energy of the lowest level in the excited SD band 6 is 14,239 keV. The spin and parity of this state has been determined to be either 29− or 31−. The measured properties of SD band 6 are consistent with an interpretation in terms of a rotational band built on an octupole vibration. A comparison with an RPA calculation by Nakatsukasa et al. suggests that the spin of the lowest SD band 6 level is 31−.

Lifetimes of states in the lowest lying positive parity band in 106Cd have been measured using the Doppler shift attenuation method. The deduced B(E2) transition rates show a marked decrease with increasing spin. Cranking and semiclassical model calculations suggest that the structure has the character of a shears-type band resulting from the coupling of g(9/2) proton holes to aligned pairs of h(11/2) and g(7/2) neutron particles. This is the first clear evidence for the phenomenon of "antimagnetic" rotation in nuclei.

The excitation energy, spin and parity of the yrast superdeformed band 1 in 152Dy have been established. The evidence comes mainly from the measured properties of a 4011 keV single‐step transition connecting the yrast superdeformed level fed by the 693 keV transition to the 27− yrast state. Four additional, weaker, linking γ rays have been placed as well. The excitation energy of the lowest superdeformed band 1 member is 10,644 keV and its spin and parity are determined to be 24+. A further nine transitions of dipole character have been identified, which connect the excited superdeformed band 6 in 152Dy to the yrast SD band 1. The excitation energy of the lowest level in the excited SD band 1 is 14,239 keV. The lowest state in band 6 has been determined to be of negative parity and odd spin (29− or 31−). The measured properties of band 6 are consistent with an interpretation in terms of an octupole vibrational band. A comparison with an RPA calculation by Nakatsukasa et al. suggests that the spin of the lowest SD band 6 level is 31−.

An isomer with a half-life of 15 +/- 1 mus has been observed in the N = 74 nucleus Sm-136, populated following the reaction (Ag(S,p2n)Sm)-Ag-107-S-32-Sm-136. It is proposed to have a K(pi) = 8- two quasineutron configuration. The isomer decays via a DELTAK = 8, 466 keV E1 transition with a surprisingly low hindrance per degree of K forbiddenness, f(nu) = 25.

The yrast structure of 207Pb above the 13/2+ isomeric state has been investigated in deep-inelastic collisions of 208Pb and 208Pb at ATLAS, Argonne National Laboratory. New and previously observed transitions were measured using the Gammasphere detector array. The level scheme of 207Pb is presented up to ~ 6 MeV, built using coincidence and γ-ray intensity analyses. In addition, the spin and parity assignments of states were made, based on angular distributions and comparisons to shell model calculations.

Correlations of decays above and below isomeric states in the normally deformed minimum of 192Pb have been used to identify discrete transitions in the decay of the superdeformed (SD) band. The data establish the absolute excitation energy of the lowest observed SD level as 4.425 MeV. Extrapolation to the bandhead indicates that the excitation energy of the superdeformed well in 192Pb is 0.5 MeV lower than in the heavier isotope 194Pb. The results confirm the trend to decreasing excitation energy with decreasing neutron number predicted by both a macroscopic Strutinsky method approach and microscopic mean field calculations.

Evidence is presented for multiphonon excitations based on a high-spin (25 Planck) intrinsic state in the deformed nucleus 182 Os. Angular momentum generation by this mode competes with collective rotation. The experimental data are compared with tilted-axis cranking calculations, supporting the vibrational interpretation. However, the lower experimental energies provide evidence that more complex interactions of states are playing a role.

The excitation energy, spin, and parity of the yrast superdeformed band in 152Dy have been firmly established. The evidence comes mainly from the measured properties of a 4011 keV single-step transition connecting the yrast superdeformed level fed by the 693 keV transition to the 27- yrast state. Four additional, weaker, linking gamma rays have been placed as well. The excitation energy of the lowest superdeformed band member is 10 644 keV and its spin and parity are determined to be 24+.

Professor George Dracoulis, a pillar of the Australian National University's Department of Nuclear Physics and a highly respected researcher internationally, passed away on 19 June 2014, after a brief battle with an aggressive kidney cancer.

The intrinsic quadrupole moment Q(0) of superdeformed rotational bands in A approximately 150 nuclei depends on the associated single-particle configuration. We have derived an empirical formula based on the additivity of effective quadrupole moments of single-particle orbitals that describes existing measurements from (142)Sm to (152)Dy. To further test the formula, the predicted Q(0) moments for two superdeformed bands in (146)Gd of 14.05 eb were confronted with a new measurement yielding 13.9+/-0.4 eb and 13.9+/-0.3 eb, respectively. This excellent agreement provides empirical evidence of extreme single-particle behavior in highly deformed, collective systems.

The gamma-ray decay of excited states of the two-proton hole nucleus, 206Hg, has been identified using Gammasphere and 208Pb+238U collisions. The yrast states found include a T(1/2) = 92(8) ns 10(+) isomer located above the known 5(-) isomer. The B(E2;10(+)--8(+)) strength is used to derive the quadrupole polarization charge induced by the h(11/2) proton hole. Also, the implied quadrupole moment has been used to provide an absolute scale for the electric field gradient of Hg in Hg metal.

Our purpose was to evaluate whether bladder transplantation (BTx) can be used for bladder augmentation (BA).Bladders from infantile Brown-Norway rats (less than 21 days old) were excised and each transplanted into a pouch created in the distal omentum of a 6-week-old Lewis rat (fully allogeneic BTx). No immunosuppressant was used in group I (n=12). Intramuscular FK506 was used daily from the day of BTx in group II (n=16; 0.2 mg/kg), group III (n=22; 0.6 mg/kg), and group IV (n=16; 1.2 mg/kg) until harvesting 3, 4, 5, or 6 weeks after BTx. FK506 was used for only 2 weeks in group V (n=12; 0.6 mg/kg/day) and group VI (n=12; 1.2 mg/kg/day). Syngeneic bladder transplants acted as controls (n=16). Hematoxylin and eosin staining was used to examine all grafts. In six rats from group III, BA was performed by anastomosing the graft to the recipient bladder 10 days after BTx.Each successfully transplanted graft appeared macroscopically as a thin-walled cyst. Rejection was seen in all grafts from groups I, II, V, and VI, and was minimal or absent in groups III and IV. On medium to long-term follow-up the only side effect of FK506 observed was reduced weight gain. Graft survival in the control group was 100%. BA was successful in all six cases, and the mucosa was normal throughout each augmented bladder.This is the first report of the successful transplantation of infantile tissue without vascular anastomosis. Because of the efficient, safe immunosuppression possible with FK506, our BTx technique could find clinical application for creating viable vesical tissue that could be used for BA.

High-spin states in the near proton-dripline nucleus {sup 107}Sb have been identified, and collectivity in this nucleus has been observed for the first time in the form of two rotational bands. One of the observed rotational structures is a {delta}I=1 band, and is interpreted as based on a {pi}(g{sub 9/2}){sup -1}(multiply-in-circle sign){pi}(g{sub 7/2}d{sub 5/2}){sup 2} proton configuration. A second structure has {delta}I=2 character, and is explained as being based on a {pi}h{sub 11/2}(multiply-in-circle sign)[{pi}(g{sub 9/2}){sup -2}(multiply-in-circle sign){pi}(g{sub 7/2}d{sub 5/2}){sup 2}] proton configuration through comparison with cranked Nilsson-Strutinsky model calculations. The calculations predict that this band terminates at a spin of 79/2 ({Dirac_h}/2{pi}). (c) 2000 The American Physical Society.

A level scheme is presented for ${}_{53}^{111}\mathrm{I},$ populated by the ${}^{58}\mathrm{Ni}{(}^{58}\mathrm{Ni},\ensuremath{\alpha}p)$ reaction. A backed-target experiment, at a low beam energy of 210 MeV, was performed using the JUROSPHERE spectrometer, while a thin-target experiment at 250 MeV was performed using the GAMMASPHERE spectrometer in conjunction with the MICROBALL charged-particle detector array. The new level scheme fits well the systematics of light iodine nuclei and provides evidence for a terminating band at the highest spins. Low-lying transitions previously assigned to ${}^{111}\mathrm{I}$ could not be confirmed.

High-spin states were populated in ${}^{108}\mathrm{Cd}$ using the ${}^{96}\mathrm{Zr}{(}^{16}\mathrm{O},4n)$ reaction at a beam energy of 72 MeV. Two magnetic dipole bands have been observed, both of which contain weak $E2$ crossover transitions. Lifetimes for the stronger of the two bands were measured via the Doppler shift attenuation method. The configuration assignment for this band has been determined from comparison with tilted axis cranking model calculations to be $\ensuremath{\pi}[{g}_{9/2}^{\ensuremath{-}3}{g}_{7/2}]\ensuremath{\bigotimes}\ensuremath{\nu}[{h}_{11/2}{(g}_{7/2}{d}_{5/2}{)}^{1}]$ and $\ensuremath{\pi}[{g}_{9/2}^{\ensuremath{-}3}{g}_{7/2}]\ensuremath{\bigotimes}\ensuremath{\nu}[{h}_{11/2}^{3}{(g}_{7/2}{d}_{5/2}{)}^{1}],$ before and after the $\ensuremath{\nu}{h}_{11/2}^{2}$ band crossing, respectively. The deduced $B(M1)$ strengths decrease rapidly with increasing spin after the $\ensuremath{\nu}{\mathrm{h}}_{11/2}^{2}$ alignment, which is a characteristic behavior of a shears band.