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Background: The aim of the study is to comprehensively report on a single tertiary referral center experience with the use of ureteric stents, assess complication burden and determine risk factors to further inform institutional practice. Materials and Methods: The retrospectively analyzed cohorts includes 529 patients treated over a 12 months period. Data regarding details of the index pathology, stent characteristics and complications were collected retrospectively. Results: Most stents (58.9%) were used in the context of stone surgery. Stent encrustation occurred in 14.5% of patients and sepsis in 4.3%. There was a statistically significant difference between the complications of the stents removed after 90 days and the rest of the cohort. Infectious complications were more frequent in diabetic patients and in patients with chronic renal impairment. At our institution, we managed to avoid forgotten stents and catastrophic complications. Conclusion: Stent complications are the complex outcome of interplay between the foreign body and the collecting system environment, influenced by the nature and timing of surgery. Longer stent dwelling times are associated with increased complications rates, especially in patients with significant comorbidities.

To investigate the low-spin structure of 84Sr and 86Sr, two fusion-evaporation experiments using the (p,2n) reaction have been performed. The data have been evaluated in terms of γ-ray spectroscopy, i.e. the level scheme was built up, branching intensities were determined, nuclear state spin and parity assignments were made after γγ angular correlation analyses. The previously known level scheme information was extended. In addition, lifetimes were determined by means of the Doppler Shift Attenuation Method (DSAM). In 86Sr, a new method for lifetime determinations, the Spectral Difference Method (SDM), was applied for the first time. In cases where all necessary input variables were known, reduced transition strengths were calculated with Monte Carlo simulated probability density functions. It is stressed that linear error propagation for the calculated errors of reduced transition strengths is not universally applicable. As both nuclei lie in the vicinity of the N=50 neutron shell closure and on a possible proton subshell closure of the 2 p 3 / 2 orbital at Z=38, Nuclear Shell Model calculations for 84Sr, 86Sr, and 88Sr have been performed in the truncated ( 2 p 3 / 2 , 1 f 5 / 2 , 2 p 1 / 2 , 1 g 9 / 2 ) model space for protons and neutrons with the empirical JUN45 residual interaction. The comparison between experimental results and theoretical predictions show a large degree of consistency.

Excited low-spin states in Mo-96 and Mo-98 have been studied in gamma gamma angular correlation experiments in order to determine spins and multipole mixing ratios. Furthermore, from a Doppler lineshape analysis effective lifetimes tau in the femtosecond range were obtained. The experimental data show a complex spectrum due to configuration mixing, which is confirmed by Interacting Boson Model calculations based on a Skyrme energy density functional. The M1-transition strengths of transitions depopulating excited 2(+) states to the first 2(+) state are discussed in terms of the proton neutron mixed symmetry. (C) 2016 Elsevier B.V. All rights reserved.

The small anode germanium (SAGe) Well detector from Canberra Industries with a cosmic veto supression system was tested on marine particles and water samples. The cosmic-veto suppression system reduced the shielded background by an average of 35 % across the energy spectrum. The enhanced energy resolution and efficiency improved the ability to separate the major U-238 decay chain energies 92, 238 and 241 keV c rays as well as separate the Cs-134 peak at 604 keV from the 609 keV c- ray line of Bi-214. The SAGe Well detector with cosmic- veto suppression system has shortened counting times and increased sample throughput.

The B(E2) excitation strength of the first excited 2(+) state in even-even nuclei should directly correlate with the size of the valence space and maximize at mid-shell. A previously found saturation of B(E2) strengths in well-deformed rotors at mid-shell is tested through high-precision measurements of the lifetimes of the lowest-lying 2(+) states of the Hf-168 and W-174 rare earth isotopes. Measurements were performed using fast LaBr3 scintillation detectors. Combined with the recently remeasured B(E2; 2(1)(+) -> 0(1)(+)) values for Hf and W isotopes the new data remove discrepancies observed in the differentials of B(E2) values for these isotopes.

Background: One-phonon mixed-symmetry quadrupole excitations are a well-known feature of near-spherical, vibrational nuclei. Their interpretation as a fundamental building block of vibrational structures is supported by the identification of multiphonon states resulting from a coupling of fully-symmetric and mixed-symmetric quadrupole phonons. In addition, the observation of strong M1 transitions between low-lying 3(-) and 4(+) states has been interpreted as an evidence for one-phonon mixed-symmetry excitations of octupole and hexadecapole character. Purpose: The aim of the present study is to identify collective one-and two-phonon excitations in the heaviest stable N = 52 isotone Ru-96 based on a measurement of absolute M1, E1, and E2 transition strengths. Methods: Inelastic proton-scattering experiments have been performed at the Wright Nuclear Structure Laboratory (WNSL), Yale University, and the Institute for Nuclear Physics (IKP), University of Cologne. From the acquired proton-gamma and gamma gamma coincidence data we deduced spins of excited states, gamma-decay branching ratios, and multipole mixing ratios, as well as lifetimes of excited states via the Doppler-shift attenuation method (DSAM). Results: Based on the new experimental data on absolute transition strengths, we identified the 2(+) and 3(+) members of the two-phonon mixed-symmetry quintuplet (2(1,ms)(+) circle times 2(1,s)(+)). Furthermore, we observed strong M1 transitions between low-lying 3(-) and 4(+) states suggesting one-phonon symmetric andmixed-symmetric octupole and hexadecapole components in their wave functions, respectively. The experimental results are compared to sdg-IBM-2 and shell-model calculations. Conclusions: Both the sdg-IBM-2 and the shell-model calculations are able to describe key features of mixed-symmetry excitations of Ru-96. Moreover, they support the one-phonon mixed-symmetry hexadecapole assignment of the experimental 4(2)(+) state.

We report on the first experiment combining the Recoil Distance Doppler Shift technique and multistep Coulomb excitation in inverse kinematics at beam energies of 3–10 A MeV. The setup involves a standard plunger device equipped with a degrader foil instead of the normally used stopper foil. An array of particle detectors is positioned at forward angles to detect target-like recoil nuclei which are used as a trigger to discriminate against excitations in the degrader foil. The method has been successfully applied to measure lifetimes in 128Xe and is suited to be a useful tool for experiments with radioactive ion beams.

The preliminary results from the RISING Stopped Beam Isomer Campaign are presented, with specific focus on results of the initial experiment to investigate isomeric decays along the N=Z line around A similar to 80-90 following the projectile fragmentation of a Ag-107 primary beam at an energy of 750 MeV per nucleon. A description of the technical aspects behind the design of the RISING array is presented, together with evidence for previously unreported isomeric decays in Tc-87,Tc-88 and the N=Z nuclei Nb-82(41) and Tc-86(43).

Background: Excitations with mixed proton-neutron symmetry have been previously observed in the $N=52$ isotones. Besides the well established quadrupole mixed-symmetry states (MSS), octupole and hexadecapole MSS have been recently proposed for the nuclei $^{92}$Zr and $^{94}$Mo. Purpose: The heaviest stable $N=52$ isotone $^{96}$Ru was investigated to study the evolution of octupole and hexadecapole MSS with increasing proton number. Methods: Two inelastic proton-scattering experiments on $^{96}$Ru were performed to extract branching ratios, multipole mixing ratios, and level lifetimes. From the combined data, absolute transition strengths were calculated. Results: Strong $M1$ transitions between the lowest-lying $3^-$ and $4^+$ states were observed, providing evidence for a one-phonon mixed-symmetry character of the $3^{(-)}_2$ and $4^+_2$ states. Conclusions: $sdg$-IBM-2 calculations were performed for $^{96}$Ru. The results are in excellent agreement with the experimental data, pointing out a one-phonon hexadecapole mixed-symmetry character of the $4^+_2$ state. The $\big< 3^-_1||M1||3^{(-)}_2\big>$ matrix element is found to scale with the $$ matrix element.

In addition to the well-established quadrupole mixed-symmetry states, octupole and hexadecapole excitations with mixed-symmetry character have been recently proposed for the N = 52 isotones 92Zr and 94Mo. We performed two inelastic proton-scattering experiments to study this kind of excitations in the heaviest stable N = 52 isotone 96Ru. From the combined experimental data of both experiments absolute transition strengths were extracted.

A $\gamma\gamma$ angular correlation experiment has been performed to investigate the low-energy states of the nucleus $^{98}$Mo. The new data, including spin assignments, multipole mixing ratios and lifetimes reveal evidence for shape coexistence and mixing in $^{98}$Mo, arising from a proton intruder configuration. This result is reproduced by a theoretical calculation within the proton-neutron interacting boson model with configuration mixing, based on microscopic energy density functional theory. The microscopic calculation indicates the importance of the proton particle-hole excitation across the Z=40 sub-shell closure and the subsequent mixing between spherical vibrational and the $\gamma$-soft equilibrium shapes in $^{98}$Mo., Comment: 6 pages, 5 figures, 3 tables; published in Phys. Rev. C

The half-life of the yrast I π = 2+ state in the neutron-rich nucleus 188W has been measured using fast-timing techniques with the HPGe and LaBr3:Ce array at the National Institute of Physics and Nuclear Engineering, Bucharest. The resulting value of t1/2 = 0.87(12) ns is equivalent to a reduced transition probability of B(E2; 2+ 1 → 0+ 1 ) = 85(12) W.u. for this transition. The B(E2; 2+ 1 → 0+ 1 ) is compared to neighboring tungsten isotopes and nuclei in the Hf, Os, and Pt isotopic chains. Woods-Saxon potential energy surface (PES) calculations have been performed for nuclei in the tungsten isotopic chain and predict prolate deformed minima with rapidly increasing γ softness for 184–192W and an oblate minimum for 194W.

The neutron-rich nucleus 117Rh was synthesized in the fission of a relativistic 238U beam produced at the GSI laboratory in Darmstadt, Germany. An isomeric state with t1/2=138(17) ns decaying by a single γ ray was observed, providing the first information on the excited states in this nucleus. The experimental data are discussed in terms of systematics and interpreted by using the Woods-Saxon deformed shell model and triaxial-rotor-plus-particle calculations. The origin of the isomer is explained as being due to a hindered E2 transition to the ground state.

Background: The interplay between single-particle and collective excitations in the 30 ≤Z≤ 40 and 30 ≤N≤ 50 even-even isotopes has been examined in light of recent new measurements of magnetic moments of 41+, 22+, and 21+ states. Purpose: The g factors of the 41+ and 22+ states in the 72,74,76Ge isotopes have been measured for the first time and the g(21+) values have been remeasured. Methods: The transient field (TF) technique in inverse kinematics with a variety of targets has been applied, following Coulomb excitation of the relevant states. The data have been analyzed within the framework of the IBA-II model. Large-scale shell-model calculations have been performed within the p3/2,p1/2,f 5/2,g9/2 orbital space for both protons and neutrons with the JUN45 and JJ4B interactions. Results: The measured Ge g factors were compared to the g factors of the low-lying states of the neighboring Zn, Ge, Se, Kr, and Sr isotopes. The results were evaluated in the context of the systematics of g factors in the A∼80 region. Conclusions: The predictions based on the classic collective model and the interacting boson model IBA-II agree with the experimental results. No evidence for shell closure was found for neutrons at N=38 or N=40. © 2013 American Physical Society.

In all applications of gamma-ray spectroscopy, one of the important parts of the data analysis is to measure the detection efficiency which depends on the geometrical conditions of the source-detector arrangement. As the samples commonly measured can vary greatly in volume and shape, it is impractical to manufacture standard sources for large and complex measurement items and packaging's for the purpose of efficiency calibration. Canberra Industries developed the mathematical efficiency software called In Situ Object Calibration Software (ISOCS) to overcome the difficulties presented above. Recently, Canberra has extended the capability of ISOCS and has developed a software package for the International Atomic Energy Agency (IAEA) that simplifies, automates, and optimizes mathematical efficiency analysis for a given set of experimental parameters. The new optimization software called the “Advanced-ISOCS” varies the “not well known” parameters of the source geometry within user specified intervals and determines the optimal efficiency. The efficiency optimization capability is carried out using either a random search based on standard probability distributions or using numerical technique that carry out more directed search. The radionuclide mass is determined using the optimum efficiency and compared against the known mass. Results of optimizations carried out using the numerical technique are presented in this paper.

The near-yrast structure of the near-magic, odd-odd nucleus, ${}_{39}^{88}$Y${}_{49}$, has been studied into the high-spin regime. Investigations were performed at the Wright Nuclear Structure Laboratory, Yale University, using the ${}^{74}$Ge(${}^{18}$O,$p3n$) and ${}^{76}$Ge(${}^{18}$O,$p5n$) fusion-evaporation reactions at beam energies of 60 and 90 MeV, respectively. Gamma-ray energy coincidence analyses using both double (${\ensuremath{\gamma}}^{2}$) and triple (${\ensuremath{\gamma}}^{3}$) fold coincidences, together with angular correlation measurements, have been used to extend the previously reported level scheme to an excitation energy of 8.6 MeV and a spin and parity of 19${}^{(\ensuremath{-})}$. The presented level scheme is compared with predictions of a truncated valence space shell-model calculation, which assumes an inert ${}^{56}$Ni core with proton and neutron excitations allowed within the ${f}_{5/2}$, ${p}_{3/2}$, ${p}_{1/2}$, and ${g}_{9/2}$ single-particle states. The shell-model calculations show a reasonable comparison with the experimental data for the yrast, positive-parity states up to spin 18 $\ensuremath{\hbar}$, with larger variations evident for negative-parity states with spins greater than 16 $\ensuremath{\hbar}$. In spite of a significant increase in angular momentum input associated with the thin target ${}^{76}$Ge(${}^{18}$O,$p5n$) reaction channel, as compared to the backed target data using the ${}^{74}$Ge target, no additional discrete states were identified in the former data set, suggesting that the level scheme for this nucleus fragments significantly above the observed states, possibly indicating cross-shell excitations becoming dominant for $Ig$19 $\ensuremath{\hbar}$.

Neutron-rich silver isotopes were populated in the fragmentation of a 136Xe beam and the relativistic fission of 238U. The fragments were mass analyzed with the GSI Fragment Separator and subsequently implanted into a passive stopper. Isomeric transitions were detected by 105 high-purity germanium detectors. Eight isomeric states were observed in 122-126Ag nuclei. The level schemes of 122,123,125Ag were revised and extended with isomeric transitions being observed for the first time. The excited states in the odd-mass silver isotopes are interpreted as core-coupled states. The isomeric states in the even-mass silver isotopes are discussed in the framework of the proton-neutron split multiplets. The results of shell-model calculations, performed for the most neutron-rich silver nuclei are compared to the experimental data. © 2013 American Physical Society., Spanish Ministerio de Ciencia e Innovación under conctracts FPA2009-13377-C02-02 and FPA2011-29854-C04-01 and the Spanish Consolider-Ingenio 2010 Programme CPAN (CSD2007-00042).

The half-life of the Iπ=6+ yrast state at Ex=2294 keV in 138Ce has been measured as T1/2=880(19) ps using the fast-timing γ-ray coincidence method with a mixed LaBr3(Ce)-HPGe array. The excited states in 138Ce have been populated by the 130Te(12C,4n) fusion-evaporation reaction at an incident beam energy of 56 MeV. The extracted B(E2;61+→41+)=0.101(24) W.u. value is compared with the predictions of truncated basis shell model calculations and with the systematics of the region. This shows an anomalous behavior compared to the neighboring isotonic and isotopic chains. Half-lives for the yrast 5-, 11+ and 14+ states in 138Ce have also been determined in this work.

Excited states in 74Se were populated following the e/β + decay of 74Br, mainly from the J=K=4, 13.8-keV β-decaying isomer. Off-beam γ-ray spectroscopy was performed with the array of Clover HPGe detectors at WNSL Yale. Many new transitions were observed and rigorous spin assignments were made based on γ-γ angular correlations. The β-decay strength was found to proceed almost entirely to a few high-lying states near 4500 keV, which are consistent with deformed two-quasineutron high-K configurations. These doorway states then provide an effective tool for populating and identifying the lower prolate structures. Once categorized, the low-lying states of 74Se can be described as a set of near-spherical vibrational levels mixing strongly with a spectrum of prolate states which have an unperturbed bandhead near 1350 keV. © 2013 American Physical Society.

Precise electromagnetic transition matrix elements in 10Be and 10C have provided surprisingly stringent tests of modern ab initio calculations using realistic nuclear forces. The analog transition in 10B can further constrain these new calculations and probe the symmetry of the wave functions across the A=10 multiplet. We report on a careful measurement of the γ-ray intensities from states populated in the 10B(p,p) reaction at 10 MeV, including a determination of the key E2 branch from the J=2 T=1 state at 5164keV to the J=0 T=1 state at 1740keV of 0.16(4)%. © 2012 American Physical Society.

We present results from stopped beam rare isotope spectroscopic investigations at the GSI (RISING) experiment based on the detection of gamma-ray transitions following the beta decay of Pd-94. A comparison between the measured low-lying level scheme of Rh-94 and the prediction from shell-model calculations reveals the important roles of the g(7/2) and g(9/2) orbitals in explaining the structural features. The low values of the Gamow-Teller strengths B(GT) can be attributed to the influence of the neutron-proton interaction, which gives rise to an increased seniority mixing for the nuclear states, thereby leading to a fragmentation of the strength to several daughter levels. These results provide further strong indications that Pd-94 resides in the middle of a structural transition region in the Pd isotopes as the N = Z line is approached.

To study how collective nuclear structure evolves towards mid-shell and test next-generation LaBr3 (Ce) scintillation detectors, measurements of the lifetimes of 21 + states in 168 Hf and 174 W were conducted at the Wright Nuclear Structure Laboratory. Preliminary results indicate that the excellent time and energy resolution of LaBr3 detectors make them well suited to fast timing measurements, allowing for improved background subtraction and peak resolution in comparison to BaF2 detectors. Preliminary analysis shows an order of magnitude reduction in the statistical error of the 2+ lifetimes in comparison to literature values for both nuclei. In the case of 174 W, a substantial reduction of the observed lifetime hints at the possibility of new physics in the region.

Background: The evolution of and interplay between single-particle and collective excitations in the 40 $\ensuremath{\leqslant}N\ensuremath{\leqslant}$ 50 range for ${}_{38}$Sr and ${}_{40}$Zr isotopes have been studied.Purpose: Measurement of the $g$ factor of the 2${}_{1}^{+}$ and 4${}_{1}^{+}$ states in radioactive ${}^{88}$Zr while simultaneously remeasuring the $g({2}_{1}^{+})$ factors in the Sr isotopes and extention of the measurements to higher energy states in the Sr isotopes. Lifetimes of states in these nuclei are determined.Methods: The transient field technique in inverse kinematics and line-shape analysis using the Doppler-shift attenuation method are applied. The ${}^{88}$Zr nuclei were produced by the transfer of an $\ensuremath{\alpha}$ particle from the ${}^{12}$C nuclei of the target to ${}^{84}$Sr nuclei in the beam. The excited states in the stable ${}^{84}$Sr isotopes were simultaneously populated via Coulomb excitation by ${}^{12}$C in the same target. Coulomb excitation measurements on ${}^{86,88}$Sr were carried out with the same apparatus.Results: The resulting $g$ factors and $B(E2)$ values of these nuclei reveal similarities between the two chains of Zr and Sr isotopes. Large-scale shell-model calculations were performed within the ${p}_{3/2},{f}_{5/2},{p}_{1/2},{g}_{9/2}$ orbital space for both protons and neutrons and yielded results in agreement with the experimental data.Conclusions: In this paper the magnetic moments and lifetimes of several low-lying states in ${}^{88}$Zr and ${}^{84.86,88}$Sr have been measured and compared to large-scale shell-model calculations.

The $g$ factor of the ${2}_{1}^{+}$ state of ${}^{168}$Hf was measured using the perturbed angular correlation technique in a static external magnetic field. The result, $g({2}_{1}^{+})=0.17(3)$, is discussed in relation to the systematics of the previously reported $g$ factors in the Hf isotopes and compared to the predictions of several models. An interesting outcome of the analysis presented in this paper has to do with the relatively small result for the $g$ factor. This indicates that in the Hf isotopes, a minimum in the $g$(${2}_{1}^{+}$) dependence on $N$ occurs at $N\ensuremath{\le}98$ and not at midshell, as expected from IBA-2 or large-scale shell-model calculations. The pairing plus quadrupole model of Kumar and Baranger predicts a minimum at $N=98$ and gives the best description of the experimental data. The present result clearly shows the importance of $g$-factor measurements in ``fine-tuning'' among different models.

Background: The experimental study of $g(Ig2)$ factors of nuclear states can provide information about the evolution of collectivity in certain regions of the nuclear chart, and assist in obtaining a microscopic description of the nuclear wave functions. The measurements and explanations of $g(Ig2)$ factors are still a challenge for experiments and theory.Purpose: Measurement of the $g({2}_{1}^{+})$ and $g({4}_{1}^{+})$ factors, the latter for the first time, in the ${\phantom{\rule{0.16em}{0ex}}}_{44}^{96}$Ru nucleus. Comparison of the experimental results with calculations using the shell model and collective models.Methods: The experiments made use of the transient field technique, using a Coulomb-excitation reaction in inverse kinematics. Large scale shell model calculations were performed; comparisons with previous theoretical predictions, using the tidal-wave model and the hydrodynamical model, were carried out.Results: The values of $g({2}_{1}^{+})=+0.46(2)$ and $g({4}_{1}^{+})=+0.58(8)$ were experimentally obtained. While the $g({2}_{1}^{+})$ value agrees with the hydrodynamical model prediction of $g=Z/A=+0.46$, the $g({4}_{1}^{+})$ is in agreement with the shell model predictions. The trend of the experimental $g$ factors, as a function of nuclear spin, is not reproduced by the theoretical models discussed.Conclusions: Measurements of $g({2}_{1}^{+})$ and $g({4}_{1}^{+})$ in ${}^{96}$Ru were performed. Further theoretical efforts are necessary to explain the trend of the $g$ factors as a function of nuclear spin for the ${}^{96}$Ru nucleus. Future measurements of $g({4}_{1}^{+})$ should reduce the uncertainty of the result.

We measured the lifetimes of the ${2}_{1,2}^{+}$ and ${4}_{1}^{+}$ states in ${}^{98}$Ru in order to reduce their uncertainties and resolve the discrepancies in the literature for the lifetime of the ${4}_{1}^{+}$ state. Coulomb excitation in inverse kinematics was used to populate excited states in ${}^{98}$Ru, and the recoil distance doppler shift (RDDS) method was employed using the nNew Yale plunger device (NYPD). This technique combined with inverse Coulomb excitation requires several corrections due to relativistic and deorientation effects but yields high precision lifetimes. The determined ${B}_{4/2}=B({4}_{1}^{+}\ensuremath{\rightarrow}{2}_{1}^{+})/B({2}_{1}^{+}\ensuremath{\rightarrow}{0}_{1}^{+})=1.86(16)$ agrees well with the vibrational limit. In order to analyze the data, a new method for the deorientation correction of RDDS data was developed using the perturbation of experimental angular correlations. The simultaneous measurement of deorientation and lifetime of a given state and its application are discussed. The method is suitable for radioactive beam experiments.

The method of simultaneous lifetime and g factor measurements using a plunger device and the RDDS and TDRIV techniques is introduced. Results on lifetimes and hyperfine-interaction parameters for 2+1 states in 104-108Pd, 96,98,104Ru, and 92,94Zr, using a plunger device. Another method to obtain electromagnetic matrix elements is direct cross section measurements using NRF. The method is outlined, and some recent results on 76Se are shown.

We measured lifetimes and hyperfine-interaction parameters for the 21+ states in 104−108Pd, 96,98,104Ru, and 92,94Zr, using a plunger device and employing the RDDS and TDRIV techniques. High accuracy lifetimes are obtained, and the measurement of relative g factors via the TDRIV technique is established from comparison to literature data.

7Li induced-reactions have been used with a 186W target to populate nuclei around A∼180-190 at the National Institute of Physics and Nuclear Engineering in Bucharest, Romania. An array of high-purity germanium (HPGe) and cerium-doped lanthanum bromide (LaBr3:Ce) detectors have been used to measure sub-nanosecond half-lives with fast-timing techniques. The yrast 2+ state in 190Os was measured to be t1/2 = 375(20)ps, in excellent agreement with the literature value. The previously unreported half-life of the 564-keV state in 189Ir has also been measured and a value of t1/2 = 540(100)ps ps obtained.

$E0$ transitions are a sensitive indicator of structure in nuclei, reflecting shape transitional regions, deformation, and intruder states. Attention has generally focused on $E0$ transitions to the ground state or low-lying yrast levels. In this paper we look at all $E0$ transitions connecting ${0}^{+}$ states in a rather general collective model. We deduce a new selection rule and map out calculated strengths throughout the spectrum. The distributions of $E0$ strengths for several different collective structures are discussed.

Neutron-rich nuclei were populated in a relativistic fission of 238U. Gamma-rays with energies of 135 keV and 184 keV were associated with two isomeric states in 121Pd and 117Ru. Half-lives of 0.63(5) microseconds and 2.0(3) micrisecondss were deduced and the isomeric states were interpreted in terms of deformed single-particle states.

Octupole vibrational states were studied in the nucleus (150)Nd via inelastic proton scattering with 10.9-MeV protons, which are an excellent probe to excite natural parity states. For the first time in (150)Nd, both the scattered protons and the gamma rays were detected in coincidence, giving the possibility to measure branching ratios in detail. Using the coincidence technique, the B(E1) ratios of the decaying transitions for 10 octupole vibrational states and other negative-parity states to the yrast band were determined and compared to the Alaga rule. The positive and negative-parity states revealed by this experiment are compared with interacting boson approximation calculations performed in the spdf boson space. The calculations are found to be in good agreement with the experimental data, for both positive and negative-parity states.

A beta-decaying high-spin isomer in Cd-96, with a half-life T-1/2 = 0.29(-0.10)(+0.11) s, has been established in a stopped beam rare isotope spectroscopic investigations at GSI (RISING) experiment. The nuclei were produced using the fragmentation of a primary beam of Xe-124 on a Be-9 target. From the half-life and the observed gamma decays in the daughter nucleus, Ag-96, we conclude that the beta-decaying state is the long predicted 16(+) "spin-gap'' isomer. Shell-model calculations, using the Gross-Frenkel interaction and the pi nu(p(1/2,)g(9/2)) model space, show that the isoscalar component of the neutron-proton interaction is essential to explain the origin of the isomer. Core excitations across the N = Z = 50 gaps and the Gamow-Teller strength, Bd(GT) distributions have been studied via large-scale shell-model calculations using the pi nu(g, d, s) model space to compare with the experimental B(GT) value obtained from the half-life of the isomer. (Less)

Heavy neutron-rich nuclei were populated via the fragmentation of a E/A = 1 GeV (208)(82)Pb beam. Secondary fragments were separated and identified and subsequently implanted in a passive stopper. By the detection of delayed gamma rays, isomeric decays associated with these nuclei have been identified. A total of 49 isomers were detected, with the majority of them observed for the first time. The newly discovered isomers are in (204,205)(80)Hg, (201,202,204,205)(79)Au, (197,203,204)(78)Pt, (195,199-203)(77)Ir, (193,197-199)(76)Os, (196)(75)Re, (190,191)(74)W, and (189)(73)Ta. Possible level schemes are constructed and the structure of the nuclei discussed. To aid the interpretation, shell-model as well as BCS calculations were performed. ©2011 American Physical Society, This work is supported by the EPSRC (UK) and AWE plc. (UK), the EU Access to Large Scale Facilities Programme (EURONS, EU Contract No. 506065), The Swedish Research Council, The Polish Ministry of Science and Higher Education, The Bulgarian Science Fund, The US Department of Energy (Grant No. DE-FG02-91ER-40609), The Spanish Ministerio de Ciencia e Innovacion under Contract No. FPA2009- 13377-C02-02, The German BMBF, The Hungarian Science Foundation, and the Italian INFN.

Excited states in Ag-96 were populated in fragmentation of an 850-MeV/u Xe-124 beam on a 4-g/cm(2) Be target. Three new high-spin isomers were identified and the structure of the populated states was investigated. The level scheme of Ag-96 was established, and a spin parity of (13(-)), (15(+)), and (19(+)) was assigned to the new isomeric states. Shell-model calculations were performed in various model spaces, including pi nu(p(1/2), g(9/2), f(5/2), p(3/2)) and the large-scale shell-model space pi nu(gds), to account for the observed parity changing M2 and E3 transitions from the (13(-)) isomer and the E2 and E4 transitions from the (19(+)) core-excited isomer, respectively. The calculated level schemes and reduced transition strengths are found to be in very good agreement with the experiment.

Isomeric states in the semimagic Sn128-130 isotopes were populated in the fragmentation of a Xe-136 beam on a Be-9 target at an energy of 750 A.MeV. The decay of an isomeric state in Sn-128 at an excitation energy of 4098 keV has been observed. Its half live has been determined to be T-1/2 = 220(30) ns from the time distributions of the delayed gamma rays emitted in its decay. gamma gamma coincidence relations were analyzed in order to establish the decay pattern of the newly established state toward the known (7(-)) and (10(+)) isomers at excitation energies of 2092 and 2492 keV, respectively. Based on a comparison with results of state-of-the-art shell-model calculations the new isomeric state is proposed to have the nu h(11/2)(-3)d(3/2)(-1) configuration with the four neutron holes in Sn-132 maximally aligned to a total spin of I-pi = 15(-).

The transient-field-perturbed angular correlation technique was used with Coulomb excitation in inverse kinematics to perform a systematic measurement of the $g$ factors of the first excited ${2}_{1}^{+}$ states in the stable even-$A$ isotopes $^{96\ensuremath{-}104}\mathrm{Ru}$. The measurements have been made relative to one another under matched kinematic conditions and include a measurement of $g({2}_{1}^{+})=+0.47(3)$ in $^{96}\mathrm{Ru}$.

The structure of $^{72}\mathrm{Se}$ was investigated following the $\ensuremath{\epsilon}/{\ensuremath{\beta}}^{+}$ decay of $^{72}\mathrm{Br}$ produced in the $^{58}\mathrm{Ni}$($^{16}\mathrm{O}$, $\mathit{pn}$) reaction at 50 MeV. Using a beam chopping system, off-beam $\ensuremath{\gamma}$-ray decay data was collected with an array of clover Ge detectors. $\ensuremath{\gamma}$-$\ensuremath{\gamma}$ coincidence measurements provided a significant modification of the prior level scheme, and $\ensuremath{\gamma}$-$\ensuremath{\gamma}$ angular correlation measurements allowed spin determinations and multipole mixing ratio extraction. The new information on the non-yrast states was combined with previous in-beam data to investigate the issue of shape coexistence by comparing to various configuration mixing approaches. Clear evidence for shape coexistence is found, with a ground state of modest, or slightly oblate, deformation and a well-deformed prolate shape that would lie at an unperturbed excitation of 875 keV. The shape mixing is near complete at low spin.