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An analysis of the capabilities of AGATA for in-beam γ -ray spectroscopy at relativistic energies is presented. AGATA's ability to determine the position of γ -ray interaction points in the Germanium crystal provides the crucial ingredient for attaining high γ -ray energy resolution when the emitting nucleus is traveling at more than half the speed of light. This is the typical velocity of exotic nuclei exiting the SuperFRS spectrometer at the future FAIR facility, where AGATA will be deployed as part of the high-resolution in-beam spectroscopy project, HISPEC. A discussion of different experimental techniques using AGATA under these conditions is presented, including analysis of the different Doppler-based methods for lifetime determination. The properties of the key reaction mechanisms expected to be applied for in-beam γ -ray spectroscopy at FAIR are discussed, along with the aspects of those reactions that can be exploited by the advanced capabilities of the AGATA array. [ABSTRACT FROM AUTHOR]

Nuclear-structure studies using fusion reactions are reviewed in terms of prospects for advancement using the next generation of γ -ray tracking arrays such as AGATA. Properties discussed include those of light N = Z nuclei and rotational behaviour in heavy nuclei at high values of angular momentum and internal excitation energy. [ABSTRACT FROM AUTHOR]

The low-lying structures of the midshell ν g 9 / 2 Ni isotopes 72 Ni and 74 Ni have been investigated at the RIBF facility in RIKEN within the EURICA collaboration. Previously unobserved low-lying states were accessed for the first time following β decay of the mother nuclei 72 Co and 74 Co. As a result, we provide a complete picture in terms of the seniority scheme up to the first ( 8 + ) levels for both nuclei. The experimental results are compared to shell-model calculations in order to define to what extent the seniority quantum number is preserved in the first neutron g 9 / 2 shell. We find that the disappearance of the seniority isomerism in the ( 8 1 + ) states can be explained by a lowering of the seniority-four ( 6 + ) levels as predicted years ago. For 74 Ni, the internal de-excitation pattern of the newly observed ( 6 2 + ) state supports a restoration of the normal seniority ordering up to spin J = 4 . This property, unexplained by the shell-model calculations, is in agreement with a dominance of the single-particle spherical regime near 78 Ni. [ABSTRACT FROM AUTHOR]

We study the mechanical response under large elastic strains of pentamode layers confined between stiffening plates, and the potential use of such systems as novel seismic isolation and impact protection devices. We analyze pentamode materials that exhibit three soft deformation modes in the infinitesimal stretching regime that follow by the presence of perfectly hinged connections between the rods. The response of these metamaterials under large elastic strains is characterized by an elastic-stiffening effect in terms of the lateral force-displacement response, which increases in the presence of rigid connections and decreases by increasing the number of layers. Our results lead us to conclude that the analyzed pentamode metamaterials can be effectively employed as novel, performance-based devices for seismic and mechanical vibration protection, by designing the lattice geometry, the stiffness properties of the joints, and the lamination scheme in a suitable manner and as a function of the operating conditions. [ABSTRACT FROM AUTHOR]

The level structures of 70 Co and 70 Ni, populated from the β decay of 70 Fe, have been investigated using β -delayed γ -ray spectroscopy following in-flight fission of a 238 U beam. The experimental results are compared to Monte-Carlo Shell-Model calculations including the p f + g 9 / 2 + d 5 / 2 orbitals. The strong population of a ( 1 + ) state at 274 keV in 70 Co is at variance with the expected excitation energy of ∼1 MeV from near spherical single-particle estimates. This observation indicates a dominance of prolate-deformed intruder configurations in the low-lying levels, which coexist with the normal near spherical states. It is shown that the β decay of the neutron-rich A = 70 isobars from the new island of inversion to the Z = 28 closed-shell regime progresses in accordance with a newly reported type of shell evolution, the so-called Type II, which involves many particle-hole excitations across energy gaps. [ABSTRACT FROM AUTHOR]

The β decays Mn 68 → Fe 68 , Mn 69 → Fe 69 and Mn 70 → Fe 70 have been measured at the RIBF facility at RIKEN using the EURICA γ spectrometer combined with an active stopper consisting of a stack of Si detectors. The nuclei were produced as fission fragments from a beam of 238 U at a bombarding energy of 345 MeV/nucleon impinging on a Be target and selected using the BigRIPS separator. Half-lives and β -delayed neutron emission probabilities have been extracted for these decays, together with first experimental information on excited states populated in 69,70 Fe. The data indicate a continuously increasing deformation for Fe isotopes up to A = 70 . This is interpreted, as for Cr isotopes, in terms of the interplay between the quadrupole correlations of the ν 1 d 5 / 2 and ν 0 g 9 / 2 orbitals and the monopole component of the π 0 f 7 / 2 – ν 0 f 5 / 2 interaction. [ABSTRACT FROM AUTHOR]

The fragmentation of relativistic uranium projectiles has been exploited at the Gesellschaft für Schwerionenforschung laboratory to investigate the β decay of neutron-rich nuclei just beyond 208Pb. This paper reports on β-delayed γ decays of 211-213Tl, 215Pb, and 215-219Bi de-exciting states in the daughters 211-213Pb, 215Bi, and 215-219Po. The resulting partial level schemes, proposed with the help of systematics and shell-model calculations, are presented. The role of allowed Gamow-Teller and first-forbidden β transitions in this mass region is discussed. [ABSTRACT FROM AUTHOR]

The transfer of passive immunity from sows to piglets is important and it is the first immune protection of the new born piglet. Improving sows immunity by adding immuno-stimulating product in sows diet can positively affect colostrum composition and transfer of immune molecules to piglets. The aim of the current study is to evaluate the benefit of a different solution, made of specific fatty acids from marine origin that have been used in human medicine for decades, for sows and piglets. Two trials were conducted in commercial farm, involving 240 sows at different periods of the year. Sows were divided in a control group, without supplementation, and a test group, supplemented with the feed additive from the 90th day of gestation to weaning. Sows body condition, piglets viability and growth were recorded. Milk immunoglobulin content was measured, as well as Aujeszky antibodies in sows and piglets blood as marker of specific immunity, and blood bactericidal activity, complement activity and lysozyme as markers of non specific immunity. No effect of the product was observed on piglets zootechnical criteria and specific immunity parameters but significant improvement of piglet non specific immunity, was observed. No difference was observed neither in the piglets blood PRRSV and PCV2 antibodies and viruses nor in Aujeszky antibodies. Blood complement activity seems to be an accurate indicator of immuno-stimulating additive efficiency. Giving alkyl-glycerol fatty acids to sows in late gestation and lactation can improve the passive immunity transfer to piglets. [ABSTRACT FROM AUTHOR]

The heavy ion reaction 22Ne+208Pb at 128 MeV beam energy has been studied using the PRISMA-CLARA experimental setup at Legnaro National Laboratories. Aim of the experiment is the measurement of elastic, inelastic and one nucleon transfer cross sections. The data are presented in parallel with similar results for the unstable 24Ne nucleus, using existing data from the reaction 24Ne+208Pb at 182 MeV (measured at SPIRAL with the VAMOS-EXOGAM setup). A comparison with angular distributions obtained by semiclassical and DWBA predictions for the quadrupole deformation parameter is also discussed. In particular, the DWBA analysis allowed to determine the Β 2C charge deformation parameter both in 22Ne and 24Ne. [ABSTRACT FROM AUTHOR]

Abstract: Neutron-rich isotopes around lead, beyond , have been studied exploiting the fragmentation of an uranium primary beam at the FRS-RISING setup at GSI. For the first time β-decay half-lives of and isotopes have been derived. The half-lives have been extracted using a numerical simulation developed for experiments in high-background conditions. Comparison with state of the art models used in r-process calculations is given, showing a systematic underestimation of the experimental values, at variance from close-lying nuclei. [Copyright &y& Elsevier]

The heavy-ion reaction 22Ne + 208Pb at 128 MeV beam energy has been studied using the PRISMA-CLARA experimental setup at Legnaro National Laboratories. Elastic, inelastic, and one-nucleon transfer differential cross sections are measured and global agreement is obtained with semiclassical and distorted-wave Born approximation (DWBA) calculations. In particular, the angular distribution of the 2+ state of 22Ne is analyzed by DWBA and a similar calculation is performed for the unstable 24Ne nucleus, using existing data from the reaction 24Ne + 208pb at 182 MeV (measured at SPIRAL with the VAMOS-EXOGAM setup). In both cases the DWBA model gives a good reproduction of the experiment, pointing to a strong reduction of the β2c charge deformation parameter in 24Ne. This follows the trend predicted for the evolution of the quadrupole deformation along the Ne isotopic chain. [ABSTRACT FROM AUTHOR]

Cross-sections of the main reaction channels for the collision Ne + Pb at 7.9MeV/u were studied using the radioactive ion beam delivered by the SPIRAL facility and the VAMOS-EXOGAM experimental set-up. Angular distributions for the elastic and inelastic channels were extracted, together with distributions for the +1 n and -1 p channels. A comprehensive description of the present data is made within the GRAZING model approach. [ABSTRACT FROM AUTHOR]

The γ-decay from the warm rotation in the transition region between order and chaos is studied in the superdeformed (SD) nuclei 151Tb and 196Pb, using the EUROBALL IV array. A number of observables, testing the decay dynamics in the SD well, are compared with predictions from a Monte Carlo simulation of the γ-decay based on microscopic calculations of discrete levels and decay probabilities. Agreement with the data is found only assuming an enhancement of the B(E1) strength around 1 MeV by a factor of 10-100, which is consistent with the evidence for octupole vibrations in both mass regions. The work shows the relevance of γ-spectroscopy in the order-to-chaos regime to highlight specific nuclear structure effects. [ABSTRACT FROM AUTHOR]

Lead-rubber isolators represent a valid and economic solution for the seismic isolation of bridge structures and modern manufacturing techniques make available large devices. Velocity effects on small to medium-scale isolators have been discussed by several authors (e.g., Clark et al., 1997; Thompson et al., 2000) as well as included in reports of experimental programs (e.g., CERF, 1999). Only recently, however, the behavior of large devices was validated under full-scale displacements, loads, and velocities. In this article, results obtained from an experimental investigation on the effects of axial load and strain rate on the performance of a full-scale lead-core elastomeric bearing for bridge applications, are reported. The bearing response was analyzed with particular attention to the variation of critical performance characteristics in order to produce a set of information that could be implemented in a physically motivated numerical model. The results, in line with additional tests performed on similar full-scale bearings at the Caltrans SRMD Testing Facility at the University of California San Diego, indicate a moderate effect of the applied vertical load but a significant effect of the strain rate and cycling on all the significant response parameters. This information should be taken into account by designers, particularly when high component of velocities are associated with the expected seismic motion. A simplified numerical model is proposed for the assessment of lead-rubber bearing performance. [ABSTRACT FROM AUTHOR]

The decay following the Coulomb excitation of 68Ni at 600AMeV has been measured using the RISING array at GSI. The 68Ni beam has been produced from the fragmentation of 86Kr at 900AMeV from the UNILACSIS on a 9Be target and selected using the Fragment Separator. After the selection of Coulomb excited 68Ni isotopes a peak centered at approximately 10.8MeV has been observed in all type of RISING γ detectors. Because of the reaction mechanism the measured peak is interpreted to have a dipole nature and to come from the Pygmy Dipole Resonance. The measured data are consistent with the predictions of the Relativistic Mean Field and the Random Phase Approximation approaches. [ABSTRACT FROM AUTHOR]

Abstract: To study the order-to-chaos transition in nuclei we investigate the validity of the K-quantum number in the excited rapidly rotating 163Er nucleus, analyzing the variance and covariance of the spectrum fluctuations of γ-cascades feeding into low-K and high-K bands. The data are compared to simulated spectra obtained using a microscopic cranked shell model. K-selection rules are found to be obeyed for decay along excited unresolved rotational bands of internal excitation energy up to around 1.2 MeV and angular momenta . At higher internal energy, from about 1.2 to 2.5 MeV, the selection rules are found to be only partially valid. [Copyright &y& Elsevier]

The selection rules on the K-quantum number in rapidly rotating warm nuclei are investigated analyzing quasi-continuum spectra feeding into low-K and high-K bands in 163Er. The data are compared to simulated spectra obtained using the band mixing model predictions including the residual interaction and a term representing the effect of the K-quantum number on the rotational energy. K-selection rules are found to be obeyed by the decay along excited unresolved rotational bands of heat energy up to around 1.2 MeV and angular momentum . In contrast, the results corresponding to higher heat energy of 1.2 to 2.5 MeV indicate that the selection rules are only partially satisfied. [Copyright &y& Elsevier]

Four experiments were conducted to investigate the feeding value of South Dakota-grown field peas (Pisum sativum L.) for growing pigs. In Exp. 1, 96 pigs (initial BW = 22 ± 3.35 kg) were allotted to four treatment groups (four pigs per pen, six replicate pens per treatment) and fed growing (0.95% Lys) and finishing (0.68% Lys) diets containing 0, 12, 24, or 36% field peas (as-fed basis). There were no differences among the treatment groups in ADG, ADFI, or G:F. Likewise, there were no differences in backfat thickness or lean meat percent among treatment groups, but pigs fed diets containing 12, 24, or 36% field peas had greater (P c 0.05) loin depths than pigs fed the control diet. In Exp. 2, 120 pigs (initial BW = 7.8 ± 1.04 kg) were allotted to four treatment groups 2 wk after weaning. Pigs were then fed diets containing 0, 6, 12, or 18% field peas (as- fed basis) during the following 4 wk. There were five pigs per pen and six replicate pens per treatment. Results of the experiment showed no differences in ADG, ADFI, or G:F among treatment groups. In Exp. 3, apparent (AID) and standardized (SID) ileal digestibility coefficients of CP and AA in field peas and soybean meal were measured using six individually penned growing pigs (initial BW = 36.5 ± 2.1 kg) arranged in a repeated 3 × 3 Latin square design. The AID for Met, Trp, Cys, and Ser, and the SID for Met, Trp, and Cys were lower (P < 0.05) in field peas than in soybean meal; but for CP and all other AA, no differences in AID or SID were observed between the two feed ingredients. Experiment 4 was an energy balance experiment conducted to measure the DE and ME concentrations in field peas and corn. Six growing pigs (initial BW = 85.5 ± 6.5 kg) were placed in metabolism cages and fed diets based on field peas or corn and arranged in a two-period switch-back design. The DE values for field peas and corn (3,864 and 3,879 kcal/kg DM, respectively) were similar, but the ME of corn was higher (P c 0.05) than the ME of field peas (3,825 vs. 3,741 kcal ME/kg DM). The results from the current experiments demonstrate that the nutrients in South Dakota-grown field peas are highly digestible by growing pigs. Therefore, such field peas may be included in diets for nursery pigs and growing-finishing pigs in amounts of at least 18 and 36%, respectively, without negatively affecting pig performance. [ABSTRACT FROM AUTHOR]

The seismic response of marginal wharf segments is considered based on simple analytical relationships, and dynamic inelastic time-history analyses. Of particular interest was the amplification of transverse displacements caused by torsional response under longitudinal excitation, and the magnitude of shear key forces developed at movement joints between adjacent wharf segments. Different assumptions were made about pile stiffness, particularly recognising the differences resulting from unequal foundation stiffness and strength in the upslope and downslope directions. Simple design recommendations were verified or calibrated against the time-history results. [ABSTRACT FROM AUTHOR]

Spectra of the yrast and excited superdeformed bands, forming the E2 quasi-continuum, are measured with the EUROBALL array for the nucleus 143Eu, in coincidence with high-energy γ-rays (Eγ>3 MeV). It is found that the intensity population of the superdeformed states is enhanced by a factor of &ap;1.6 when a coincidence with a γ-ray with energy >6 MeV is required, in reasonable agreement with the increase of the line shape of the Giant Dipole Resonance built on a superdeformed configuration. This result shows that when an high energy E1 γ-ray is involved in the decay it is more likely connected with a SD rather than a ND nucleus. In addition, the analysis of the rotational quasi-continuum suggests the presence of a superdeformed component. The data are also compared and found consistent with simulation calculations of the relative intensities of the SD states, including the E1 decay of superdeformed nature. [Copyright &y& Elsevier]

IFMIF-DONES is a powerful neutron source which is being designed with the main purpose of qualifying structural materials (EUROFER being the first candidate) to be used in DEMO and fusion power plants envisaged after it. This source relies on one high current (125 mA) deuterons beam accelerated to 40 MeV which impacts on a liquid lithium target to produce an intense neutron flux through Li(d,n) stripping reactions able to simulate the nuclear responses expected on the first wall of the reactor. The engineering design of IFMIF-DONES is presently being carried out mainly in the framework of the EUROfusion Work Package Early Neutron Source (WPENS). Since 2021, a new phase has started with the launch of the FP9 WPENS workplan whose objective is to continue advancing the engineering design of the facility, putting special effort on the experimental validation of those aspects which still need to be qualified to demonstrate the fulfillment of functional and safety requirements. The ENEA Brasimone Research Centre has been and still is strongly committed in several validation tasks concerned in particular with the lithium systems design and the Remote Handling (RH) maintenance. In this paper, an overview of the most relevant validation activities carried out in recent years or still in progress or planned at the ENEA Brasimone Research Centre in both of the aforementioned areas is presented, including the erosion/corrosion tests in the Lifus 6 loop; the nitrogen-gettering materials qualification in the ANGEL facility; and the RH and prototypes testing in the DRP laboratory for the validation of the High Flux Test Module electric connectors and the pre-heating of the Target Assembly. [ABSTRACT FROM AUTHOR]

The g factor of the 12 + K-isomer in 174 W has been measured by means of the time-differential perturbed angular distribution technique as g (12 +) = + 0.304 (11) . In addition, the half-life of the isomer has been remeasured as T 1 / 2 (12 +) = 124 (8) ns, in agreement with the literature value and confirming the anomalous hindrance F of the E2 transition to the 10 + level of the ground state band with respect to the γ -tunnelling model prediction. The measured g factor has been compared with estimates based on experimental g factors from odd-mass isotopes in the same mass region and with Nilsson model calculations. The results establish unique features of the 12 + K-isomer in 174 W, which can possess a non-pure intrinsic configuration and/or can be characterised by values of the intrinsic quadrupole moment Q 0 and the rotational g factor g R significantly different with respect to the majority of K-isomers at mass A ≈ 180 . [ABSTRACT FROM AUTHOR]

Low-lying excited states in 72Ni have been investigated in an in-flight fission experiment at the RIBF facility of the RIKEN Nishina Center. The combination of the state-of-the-art BigRIPS and EURICA setups has allowed for a very accurate study of the β decay from 72Co to 72Ni, and has provided first experimental information on the decay sequence 72Fe→72Co→72Ni and on the delayed neutron-emission branch 73Co→72Ni. Accordingly, we report nearly 60 previously unobserved γ transitions which deexcite 21 new levels in 72Ni. Evidence for the location of the so-sought-after (42+),(62+), and (81+) seniority states is provided. As well, the existence of a low-spin β-decaying isomer in odd-odd neutron-rich Co isotopes is confirmed for mass A=72. The new experimental information is compared to simple shell-model calculations including only neutron excitations across the fpg shells. It is shown that, in general, the calculations reproduce well the observed states. [ABSTRACT FROM AUTHOR]

Summary: A randomized controlled trial (RCT) was carried to evaluate the effect of a feed additive on Campylobacter contamination of broilers reared in commercial conditions. Twenty‐four broiler flocks naturally contaminated with Campylobacter were enrolled in the RCT: 12 were assigned to a control group (C) fed with a conventional finishing feed from 4 weeks of age to slaughter (around 35 days), and the other group of 12 flocks (S) was fed with a finishing feed supplemented with 250 ppm of a patented feed additive (an ion‐exchanged clay compound) previously proven to reduce Campylobacter contamination in broiler caeca under experimental conditions. Enumeration of Campylobacter colonies in caeca (8 per flock) was carried out following ISO standards before feed distribution and at slaughter. Before treatment, the caecal Campylobacter load tended to be lower in C flocks (7.1 ± 1.9 log CFU/g, CI95% [6.6–7.5]) than in S flocks (7.7 ± 1.0 log UFC/g, CI95% [7.5–7.9]) (p = .05). At slaughter, the bacterial load was similar in the S (7.7 ± 1.0 log CFU/g, CI95% [7.5–7.9]) and C groups (7.5 ± 1.2 log CFU/g, CI95% [7.2–7.8]) (p = .73). Therefore, the feed additive had no significant effect on the caecal Campylobacter load at slaughter under the tested conditions. The logistical constraints inherent in field trials and the natural variability of Campylobacter contamination in naturally infected broiler flocks make it difficult to reproduce experimental results in in situ farm conditions. RCT testing of an intervention strategy in commercial situation is therefore a key step in evaluating pre‐harvest interventions against food‐borne pathogens. [ABSTRACT FROM AUTHOR]

The hysteretic behavior of friction concave isolators is affected by the variability of the friction coefficient experienced during a seismic event. This variability is a combined function of axial load, sliding velocity and temperature rise at the sliding surface, the latter being responsible for significant friction degradation. Experimental testing and corresponding numerical models are usually focused on the monodirectional performance of the friction isolators, although multi-directional paths occur in a real earthquake scenario. In this paper, the thermo-mechanical coupled (TMC) response of friction concave isolators when subjected to bidirectional excitation is investigated in both an analytical and a numerical framework. First, a simplified phenomenological model is presented that accounts for the friction degradation due to the distance traveled via a macroscale cycling variable, based on the assumption of a uniform heat flux at the sliding interface. Then, a more sophisticated numerical investigation is performed via a TMC finite element (FE) model. A customized subroutine has been developed and implemented into the FE code to account for the local variation of the friction coefficient due to the local temperature rise and sliding velocity. The mutual interaction between mechanical and thermal response is incorporated in the proposed computational approach: the friction-induced temperature rise on the contact points and the consequent friction degradation caused by heating phenomena are analyzed as two interconnected phenomena in a recursive fashion. The friction coefficient law at the sliding interface is adjusted step-by-step and is different from node to node on the basis of the temperature distribution. Validated against experimental data, the two proposed models are used within a parametric study to scrutinize some interesting features observed in the thermo-mechanical response of friction isolators. [ABSTRACT FROM AUTHOR]

Medium spin states of light N = 50 isotones have been populated using fast neutron-induced fission of 232 Th. Online prompt γ spectroscopy has been performed using the hybrid γ spectrometer ν - Ball coupled to the LICORNE directional neutron source at the ALTO facility of IJCLab. Medium spin states of the neutron-rich nucleus 82 Ge have been investigated using γ - γ and γ - γ - γ coincidence data to exploit the resolving power of ν - Ball. Two new transitions were assigned to this nucleus and a new level was placed in the level scheme. We tentatively assigned to this new state a ( 7 + ) spin-parity, which is interpreted as a new N = 50 core breaking state. This provides further insight into the energy evolution of the N = 50 shell gap toward 78 Ni. [ABSTRACT FROM AUTHOR]

The structure of the neutron-rich bismuth isotope 217Bi has been studied for the first time. The fragmentation of a primary 238U beam at the FRS-RISING setup at GSI was exploited to perform γ-decay spectroscopy, since µs isomeric states were expected in this nucleus. Gamma rays following the decay of a f1/2 = 3 µs isomer were observed, allowing one to establish the low-lying structure of 217Bi. The level energies and the reduced electric quadrupole transition probability B(E2) from the isomeric state are compared to large-scale shell-model calculations. [ABSTRACT FROM AUTHOR]

The neutron-rich rare isotope 190W is discussed as a candidate for a prolate-oblate transitional nucleus with maximum γ -softness. The collectivity of this isotope is assessed for the first time by the measurement of the reduced E 2 transition probability of its first 2 + state to the ground state. The experiment employed the FAst TIming Array (FATIMA), comprised of 36 LaBr 3 (Ce) scintillators, which was part of the DESPEC setup at GSI, Darmstadt. The 4 1 + and 2 1 + states of 190W were populated subsequently to the decay of its 127(12) μs isomeric J π = 10 − state. The mean lifetime of the 2 1 + state was determined to be τ = 274 (28) ps, which corresponds to a B (E 2 ; 2 1 + → 0 1 +) value of 95(10) W.u. The results motivated a revision of previous calculations within an energy-density functional-based interacting boson model-2 approach, yielding E 2 transition properties and spectroscopic quadrupole moments for tungsten isotopes. From comparison to theory, the new data suggest that 190W is at the transition from prolate to oblate structure along the W isotopic chain, which had previously been discussed as a nuclear shape-phase transition. [ABSTRACT FROM AUTHOR]

Reduced transition probabilities have been extracted between excited, yrast states in the N = Z + 2 nucleus 94Pd. The transitions of interest were observed following decays of the I π = 14 + , E x = 2129 -keV isomeric state, which was populated following the projectile fragmentation of a 124Xe primary beam at the GSI Helmholtzzentrum für Schwerionenforschung accelerator facility as part of FAIR Phase-0. Experimental information regarding the reduced E2 transition strengths for the decays of the yrast 8 + and 6 + states was determined following isomer-delayed E γ 1 − E γ 2 − △ T 2 , 1 coincidence method, using the LaBr 3 (Ce)-based FATIMA fast-timing coincidence gamma-ray array, which allowed direct determination of lifetimes of states in 94Pd using the Generalized Centroid Difference (GCD) method. The experimental value for the half-life of the yrast 8+ state of 755(106) ps results in a reduced transition probability of B(E2:8 → + 6+) = 205 − 25 + 34 e2 fm4, which enables a precise verification of shell-model calculations for this unique system, lying directly between the N = Z line and the N = 50 neutron shell closure. The determined B (E 2) value provides an insight into the purity of (g 9 / 2) n configurations in competition with admixtures from excitations between the (lower) N = 3 p f and (higher) N = 4 g d s orbitals for the first time. The results indicate weak collectivity expected for near-zero quadrupole deformation and an increasing importance of the T = 0 proton-neutron interaction at N = 48. [ABSTRACT FROM AUTHOR]

The γ decay of the elusive narrow, near-threshold proton resonance in 11B was investigated at Laboratori Nazionali di Legnaro (INFN) in a particle- γ coincidence experiment, using the 6Li(6Li,p γ) fusion-evaporation reaction and the GALILEO-GALTRACE setup. No clear signature was found for a possible E1 decay to the 1/2 1 − , first-excited state of 11B, predicted by the Shell Model Embedded in the Continuum (SMEC) with a branching of 0.98 − 69 + 167 × 10 − 3 with respect to the dominant particle-decaying modes. The statistical analysis of the γ -ray spectrum provided an average upper limit of 2.37 × 10 − 3 for this γ -ray branching, with a global significance of 5 σ. On the other hand, by imposing a global confidence level of 3 σ , a significant excess of counts was observed for E = γ 9300 (20) keV, corresponding to a resonance energy of 11429(20) keV (namely 200(20) keV above the proton separation energy of 11B) and a γ -ray branching of 1.12 (35) × 10 − 3. This result is compatible with the SMEC calculations, potentially supporting the existence of a near-threshold proton resonance in 11B. [ABSTRACT FROM AUTHOR]

Abstract: Neutron-rich nuclei in the lead region, beyond , have been studied at the FRS-RISING setup at GSI, exploiting the fragmentation of a primary uranium beam. Two isomeric states have been identified in 210Hg: the isomer expected from the seniority scheme in the shell and a second one at low spin and low excitation energy. The decay strength of the isomer confirms the need of effective three-body forces in the case of neutron-rich lead isotopes. The other unexpected low-lying isomer has been tentatively assigned as a state, although this is in contrast with theoretical expectations. [Copyright &y& Elsevier]

The K hindrance to the y decay is studied in the warm rotating 174W nucleus, focusing on the weakening of the selection rules of the K quantum number with increasing excitation energy. 174W was populated by the fusion reaction of 50Ti (at 217 MeV) on a 128Te target, and-its y decay was detected by the AGATA Demonstrator array coupled to a BaF2 multiplicity filter at Laboratori Nazionali di Legnaro of INFN. A fluctuation analysis of y coincidence matrices gives a similar number of low-K and high-K discrete excited bands. The results are compared to simulations of the y-decay flow based on a microscopic cranked shell model at finite temperature in which the K mixing is governed by the interplay of Coriolis force with the residual interaction. Agreement between simulations and experiment is obtained only by hindering the £1 decay between low-AT and high-A-bands by an amount compatible with that determined by spectroscopic studies of K isomers in the same mass region, with a similar trend with excitation energy. The work indicates that K mixing due to temperature effects may play a leading role for the entire body of discrete excited bands, which probes the onset region of K weakening. [ABSTRACT FROM AUTHOR]

The deep inelastic reaction 48Ca+64Ni at 6 MeV/A has been studied using the CLARA-PRISMA setup. Angular distributions for pure elastic scattering and total cross-sections of the most relevant transfer channels have been measured. The experimental results are compared with predictions from a semiclassical model, showing good agreement for the presently analyzed few neutrons transfer channels. The &gamm;-decay of the most intense reaction products has also been studied, giving indications of the population of states with very short lifetimes. [ABSTRACT FROM AUTHOR]

The nuclear system at the limit of excitation energy and angular momentum is here studied in the case of the superdeformed nucleus 143Eu using &gama;-spectroscopy techniques. The data are based on a EUROBALL experiment using the reaction 37 Cl + 110Pd → 143Eu + 4n. The influence of thermal energy on sup erdeformed configurations is investigated through the analysis of the quasi-continuum spectra formed by E2 transitions among states of excited rotational bands with energy extending up to 4-5 MeV above the yrast line. In particular, the effective lifetimes of the discrete rotational bands forming ridge structures in γ-γ coincidence matrices is measured by a Doppler Shift Attenuation Method. The deduced quadrupole deformation of Qt &ap; 10 eb indicates that the nucleus maintains its collectivity with increasing excitation energy, supporting the superdeformed character of the excited nuclear rotation. The obtained number of sup erdeformed discrete bands forming the ridge structures is found in good agreement with microscopic cranked shell model calculations including the decay-out process into the lower deformation minimum. In addition, the nuclear properties at higher excitation energies are investigated through the E1 γ-decay of the giant dipole resonance (GDR). It is found that the intensity of the superdeformed yrast and excited bands increases by a factor of approximately 1.6 when a coincidence with a high-energy γ-ray is required, showing the importance of the E1 cooling in the feeding mechanism of the sup erdeformed states. [ABSTRACT FROM AUTHOR]

Large seismic isolation bearings and/or dampers are currently used to seismically retrofit several long-span bridges. These large devices must be thoroughly tested at full-scale with real-time seismic demands, necessitating new, larger seismic testing facilities. Accurate performance characterisation of these devices depends on thorough characterisation of the seismic testing facility itself. One component of this essential systems' characterisation is a mathematical simulation model. Although linear modelling techniques have traditionally been used to characterise seismic facilities, many of the large system's unique behaviours, parameters and non-linearities significantly reduce the accuracy of linear modelling techniques. These significant characteristics are discussed in detail. A more comprehensive non-linear modelling approach is required for these large facilities, and a simulation model using a non-linear time-history dynamic analysis approach is outlined. [ABSTRACT FROM AUTHOR]

The neutron-rich 213Pb isotope was produced in the fragmentation of a primary 1 GeV A 238U beam, separated in FRS in mass and atomic number, and then implanted for isomer decay γ -ray spectroscopy with the RISING setup at GSI. A newly observed isomer and its measured decay properties indicate that states in 213Pb are characterized by the seniority quantum number that counts the nucleons not in pairs coupled to angular momentum J = 0. The conservation of seniority is a consequence of a geometric phase associated with particle-hole conjugation, which becomes observable in semi-magic nuclei where nucleons half-fill the valence shell. The γ -ray spectroscopic observables in 213Pb are thus found to be driven by two mechanisms, particle-hole conjugation and seniority conservation, which are intertwined through a Berry phase. [ABSTRACT FROM AUTHOR]

A novel Monte Carlo technique has been developed to determine lifetimes of excited states in the tens-to-hundreds femtoseconds range in products of low-energy heavy-ion binary reactions, with complex velocity distributions. The method is based on a detailed study of Doppler-broadened γ -ray lineshapes. Its relevance is demonstrated in connection with the 18 O (7.0 MeV/u) + 181 Ta experiment, performed at GANIL with the AGATA+VAMOS+PARIS setup, to study neutron-rich O, C, N,... nuclei. Excited states in 17 O and 19 O , with known lifetimes, are used to validate the method over the ∼ 20 - 400 fs lifetime-sensitivity range. Emphasis is given to the unprecedented position resolution provided by γ -tracking arrays, which turns out to be essential for reaching the required accuracy in Doppler-shift correction. The technique is anticipated to be an important tool for lifetime investigations in exotic neutron-rich nuclei, produced with intense ISOL-type beams. [ABSTRACT FROM AUTHOR]

Target properties such as thickness and composition are essential ingredients in nuclear physics experiments, therefore, dedicated analyses to evaluate them before and/or after the measurement are often performed. In some experimental techniques, the exploited detectors allow for the evaluation of these properties on-line, i.e. directly during the experiment. In this paper, we report on the use of analysis methods coming from the Rutherford backscattering spectroscopy technique to obtain on-line information on the target used in a nuclear physics experiment. This measurement was performed at INFN LNL by exploiting the low-energy Coulomb excitation technique. The results have been compared with an independent Rutherford backscattering spectroscopy analysis of the same target performed at INFN LABEC in Florence. [ABSTRACT FROM AUTHOR]

Excited states in the neutron-rich85Se nucleus have been studied usingfor the first time a fast neutron-induced fission of 232Th. The experimentwas performed at the ALTO facility of the IPN Orsay. Coupling of the LICORNE directional neutron source with theν-ball high-resolutionγ-rayspectrometer provided unique access to high-spin states in neutron-rich fis-sion fragments from the 232Th (n,f) reaction. A preliminary level scheme of 85Se was established by the analysis of promptγ–γ–γcoincidences. Identi-fication of the all known yrast states in85Se is the first step towards studiesof more neutron-rich Se isotopes. [ABSTRACT FROM AUTHOR]

Excited states of 17N, 18N and 19N were investigated through the measurement of gamma rays, following their population via deep-inelastic reactions induced by an 18O beam (7 MeV/u) on a thick 181Ta target. The experimental setup comprised the AGATA+PARIS detection system, coupled to the VAMOS++ magnetic spectrometer. In the 17N nucleus, the analysis of gamma-ray transitions de-exciting two states around 4–5 MeV clearly pointed to discrepancies with the lifetime values reported in literature. Three new gamma rays were observed in 18N at the energies of 1662.3(3) keV, 2073.4(8) keV and 2300.9(8) keV, and hints for other two new transitions around 1566 keV and 1720 keV were found. In addition, a new transition with energy of 2489.7(8) keV was observed in 19N. [ABSTRACT FROM AUTHOR]

An experiment, aiming at measuring lifetimes of excited states in neutron-rich C and O isotopes, was performed at the GANIL laboratory with the use of the AGATA segmented HPGe tracking array, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The nuclei of interest were populated in transfer and deep-inelastic processes induced by an 18O beam at 126 MeV (7.0 MeV/u) on a 181Ta target. This paper contains a brief description of a novel implementation of a Monte-Carlo technique, which allowed us to obtain excited states lifetimes in the range from tens to hundreds femtoseconds for a reaction with complex initial velocity distribution, making use of the Doppler-shift attenuation method (DSAM). As a test case, we present here the analysis for two states in 19O: 2371-keV 9/2+ and 2779-keV 7/2+, for which lifetimes of τ > 400 fs and τ = 140+50−40 fs were obtained, respectively, in agreement with literature values. This newly developed approach will be essential for short lifetimes measurements in neutron-rich systems, exploiting intense ISOL-type beams, currently under development. [ABSTRACT FROM AUTHOR]

The “isospin mixing” phenomenon was measured by the study of the Isovector Giant Dipole Resonance (IVGDR) in 60Zn at two different excitation energies E∗ = 47 MeV and E∗ = 58 MeV. A fusion–evaporation reaction, with a beam of 30S and a target of 28Si, was used to produce the nucleus of interest. A second target of 30Si was used to produce 62Zn. For this nucleus, the mixing effect does not strongly appear in the gamma decay of the GDR and for this reason, the second reaction is necessary as reference. The experimental setup was composed of the GALILEO array (germanium detectors) coupled to large-volume LaBr3(Ce) detectors for the γ-ray measurements. An overview of the ongoing analysis and the preliminary results are presented. [ABSTRACT FROM AUTHOR]

A first performance test of the Coulomb excitation multipolarimetry (Coulex-multipolarimetry) method is presented. It is based on a 85 Br π p 3 / 2 → π p 1 / 2 spin-flip experiment performed as part of the PreSPEC-AGATA campaign at the GSI Helmholtzzentrum für Schwerionenforschung (GSI). Via determination of background levels around the expected 85 Br excitations as well as measured 197 Au excitations, an upper limit for the M1 transition strength of the 1 / 2 1 - → 3 / 2 g.s. - transition in 85 Br and a lower beam time limit for upcoming experimental campaigns utilizing Coulex-multipolarimetry have been inferred. The impact of the use of AGATA in its anticipated 1 π configuration on these estimates is deduced via Geant4 simulations. [ABSTRACT FROM AUTHOR]