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The level structures of 70Co and 70Ni, populated from the β decay of 70Fe, have been investigated using β-delayed γ-ray spectroscopy following in-flight fission of a 238U beam. The experimental results are compared to Monte-Carlo Shell-Model calculations including the pf+g9/2+d5/2 orbitals. The strong population of a (1+) state at 274 keV in 70Co 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.

A detailed study of the structure of the doubly mid-shell nucleus Dy104166170 has been carried out, following isomeric and β decay. We have measured the yrast band up to the spin-parity Jπ=6+ state, the K=2 γ-vibration band up to the 5+ state, a low-lying negative-parity band based on a 2− state that could be a candidate for the lowest energy octupole vibration state within this nucleus, and a candidate for the Kπ=6+ two quasi-particle isomer. This state was determined to have an excitation energy of 1643.91(23) keV and a half life of 0.99(4) μs, with a reduced hindrance for its decay to the ground-state band an order of magnitude lower than predicted by NpNn systematics. This is interpreted as being due to γ-vibrational mixing from a near degeneracy of the isomer and the 6+ state of the γ band. Furthermore, the parent nucleus 170Tb has been determined to have a half-life of 0.91(−13+18) s with a possible spin-parity of 2−. Keywords: K isomer, Dysprosium, Mid-shell, γ-Ray spectroscopy

The interaction cross sections (σI) of the very neutron-rich carbon isotopes 19C, 20C and 22C have been measured on a carbon target at 307, 280, and 235 MeV/nucleon, respectively. A σI of 1.280±0.023 b was obtained for 22C, significantly larger than for 19,20C, supporting the halo character of 22C. A 22C root-mean-squared matter radius of 3.44±0.08 fm was deduced using a four-body Glauber reaction model. This value is smaller than an earlier estimate (of 5.4±0.9 fm) derived from a σI measurement on a hydrogen target at 40 MeV/nucleon. These new, higher-precision σI data provide stronger constraints for assessing the consistency of theories describing weakly bound nuclei.

Groundwater seepage influences the temperature of streams and rivers by providing a relatively cool input in summer and warm input in winter. Because of this, groundwater seepage can be a determining factor in the provision of suitable water temperatures for aquatic biota. Climate warming affects stream and groundwater temperatures, and changes the thermal characteristics of streams leading to the potential disappearance of habitats. In this study the importance of groundwater for the temperature of two Dutch lowland streams and its possible role in mitigating the effects of climate change was determined by combining field measurements and a modelling experiment. Stream temperature measurements using fibre optic cables (FO-DTS) and sampling of 222Rn were done to map localized groundwater inflow. Several springs and seepage ‘hot-spots’ were located which buffered the water temperature in summer and winter. A stream temperature model was constructed and calibrated using the FO-DTS-measurements to quantify the energy fluxes acting on stream water. This way, the contribution to the stream thermal budget of direct solar radiation, air temperature and seepage were separated. The model was then used to simulate the effects of changes in shading, groundwater seepage and climate. Shading was shown to be an important control on summer temperature maxima. Groundwater seepage seemed to buffer the effect of climate warming, potentially making groundwater dominated streams more climate robust. Protecting groundwater resources in a changing climate is important for the survival of aquatic species in groundwater-fed systems, as groundwater seepage both sustains flow and buffers temperature extremes. Keywords: Stream temperature, Groundwater-surface water interaction, Distributed temperature sensing, Stream temperature model, Radon-222, Climate change

The level structure of 172Dy has been investigated for the first time by means of decay spectroscopy following in-flight fission of a 238U beam. A long-lived isomeric state with T1/2=0.71(5) s and Kπ=8− has been identified at 1278 keV, which decays to the ground-state and γ-vibrational bands through hindered electromagnetic transitions, as well as to the daughter nucleus 172Ho via allowed β decays. The robust nature of the Kπ=8− isomer and the ground-state rotational band reveals an axially-symmetric structure for this nucleus. Meanwhile, the γ-vibrational levels have been identified at unusually low excitation energy compared to the neighboring well-deformed nuclei, indicating the significance of the microscopic effect on the non-axial collectivity in this doubly mid-shell region. The underlying mechanism of enhanced γ vibration is discussed in comparison with the deformed Quasiparticle Random-Phase Approximation based on a Skyrme energy-density functional.

We have studied spallation reactions for the fission products 137Cs and 90Sr for the purpose of nuclear waste transmutation. The spallation cross sections on the proton and deuteron were obtained in inverse kinematics for the first time using secondary beams of 137Cs and 90Sr at 185 MeV/nucleon at the RIKEN Radioactive Isotope Beam Factory. The target dependence has been investigated systematically, and the cross-section differences between the proton and deuteron are found to be larger for lighter spallation products. The experimental data are compared with the PHITS calculation, which includes cascade and evaporation processes. Our results suggest that both proton- and deuteron-induced spallation reactions are promising mechanisms for the transmutation of radioactive fission products.

The decay of a new four-quasiparticle isomeric state in 160Sm has been observed using γ-ray spectroscopy at the RIBF, RIKEN. The four-quasiparticle state is assigned a 2π⊗2ν π52−[532], π52+[413], ν52−[523], ν72+[633] configuration. The half-life of this (11+) state is measured to be 1.8(4) μs. The (11+) isomer decays into a rotational band structure, based on a (6−) ν52−[523]⊗ν72+[633] bandhead, consistent with the gK−gR values. This decays to a (5−) two-proton quasiparticle state, which in turn decays to the ground state band. Potential energy surface and blocked-BCS calculations were performed in the deformed midshell region around 160Sm. They reveal a significant influence from β6 deformation and that 160Sm is the best candidate for the lightest four-quasiparticle K isomer to exist in this region. The relationship between reduced hindrance and isomer excitation energy for E1 transitions from multiquasiparticle states is considered with the new data from 160Sm. The E1 data are found to agree with the existing relationship for E2 transitions.

The β decays Mn68→Fe68, Mn69→Fe69 and Mn70→Fe70 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 238U 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 69,70Fe. 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 ν1d5/2 and ν0g9/2 orbitals and the monopole component of the π0f7/2–ν0f5/2 interaction.

ABSTRACTTacit knowledge and dilemmas experienced by youth professionals in a preventive and environment-centred approach to working with parents and childrenOn 1 January 2015 the new Youth Act, one of three recent reforms in the social domain, came into effect in the Netherlands. The Youth Act has profoundly altered the relationship between citizens/parents and professionals. While the welfare state, in which professionals play a central role, is gradually scaled down, parents and young people themselves are given a more active role in both managing and implementing the support they receive. This implies that professionals are expected to help parents implement the practice of self-management and empowerment, whereas in the past their role was to provide care for the parents and young people who were “entitled” to it. This transformation of the youth care sector is unfolding within a dynamic social context that, since 2011, has included the creation of a Youth and Family Centre (Centrum voor Jeugd en Gezin (CJG)) in every municipality. The task of these CJGs is to stimulate a positive environment for parents and children from -9 months to 23 years of age.This transformation raises questions not only for policymakers, but also for scientists and educators, and particularly for youth professionals. This contribution assesses the consequences of this transformation for the work of youth professionals who operate at the forefront in CJGs or social district teams. The nature of their work is undergoing a shift from specialist to generalist. Although the work of youth professionals remains focused on identifying early warning signs, assessing risks and supporting individual children and their families, they are now also expected to work on strengthening social cohesion in local neighbourhoods and villages. The new method of working is referred to as the “preventive and environment-centred approach”. The approach is defined as follows (Wekker, 2013). Youth professionals should:1) take account of the living conditions, lifestyle and living environment of parents and young people and invite them to use their own resources;2) strengthen social cohesion to improve the pedagogical climate in their neighbourhood;3) mobilize and/or extend the social networks of parents and young people; and4) identify risk situations and intervene where necessary to prevent escalationsThis study investigates how youth professionals working with parents and children in interdisciplinary district teams consolidate the preventive and environment-centred approach. In practice, what do they do? What are they good at? Which difficulties and dilemmas do they face? The value of this study lies in the insight it provides into the experiential knowledge of youth professionals, and the identification of points of attention for the further development of the preventive and environment-centred approach in social district teams.We investigated this issue by following experienced youth professionals working at the forefront of CJGs in their daily work. To gauge the professional knowledge of these workers, which is deeply rooted in practice, we used the concept of “tacit knowledge”, also known as experiential knowledge. The study was conducted in two CJGs in two districts of the municipality of Groningen, the Netherlands: Oosterpark and Groningen Zuid. Both CJGs include youth professionals from various organizations who work closely together. In each CJG, we selected six youth professionals who, according to their colleagues, successfully apply the preventive and environment-centred approach. Of these 12 professionals, three were male and nine female. They included five youth/social nurses, four youth workers, one paediatrician and two parenting consultants. In order to provide further depth to our observations, we conducted interviews with all 12 youth professionals. The objective of these interviews was to identify their motivations, the ways they legitimize their actions, and the dilemmas they face. Finally, the findings of our observations and interviews in each district were submitted in the context of a focus group aimed at all youth professionals from both CJGs. The objective of these focus groups was to reach a consensus regarding the knowledge, attitude and skills required of youth professionals in order to implement the preventive and environment-centred approach in their work, thus extending the applicability of this approach.Our observations clearly indicate that youth professionals are able to effectively take into account the living environment of the parents (Aspect 1) and adopt a preventive approach (Aspect 4). Aspects that are less strongly developed include the ability of youth professionals to reinforce social cohesion and, in particular, to improve the pedagogical climate of the district (Aspect 2). The network of citizens who are doing well (Aspect 3) is also not yet optimally used.In the interviews and focus groups, youth professionals identified three important obstacles. The first was lack of time (substantial case load, time involved in collaborations). The second was physical location (open doors and the vicinity of the location), and the third was selective inclusion (highly educated parents and parents who are not experiencing problems are difficult to include). A preventive and environment-centred approach is not always easy to implement. In practice, youth professionals face a number of dilemmas. First of all, there are moral dilemmas in relation to the parents’ own resources. Youth professionals are afraid that when parents seek help from within their own environment, they may actually be jumping out of the frying pan into the fire. In addition, privacy is an issue. Youth professionals are afraid of damaging fragile trust by sharing information with third parties. A methodological dilemma concerns finding the right balance between a specialist focus and a generalist focus. Time forms a third organizational dilemma, not only with respect to balancing administrative tasks, team formation, and the time needed for the families, but also with respect to a healthy balance between work and private life. Finally, the relationship between the parent organization and the interdisciplinary team is sometimes strained.The preventive and environment-centred approach appears to be a promising one for CJGs and it can and should be strengthened further. Our advice is to further develop the preventive and environment-centred approach of experienced professionals by promoting self-aware, T-shaped professionals working in an interdisciplinary context within improvised teams. Management, administration and policy should be adapted to facilitate this new way of working, particularly by offering professionals the space to further develop their skills in relation to the preventive and environment-centred approach. SAMENVATTING Ervaringskennis en dilemma’s van professionals in preventief en omgevingsgericht werken met ouders en kinderenDe transitie en transformatie in het sociale domein vraagt van jeugdprofessionals een nieuwe manier van werken, namelijk preventief en omgevingsgericht. Preventief en omgevingsgericht werken kent vier aspecten: 1. aansluiten bij de leefsituaties van ouders ter bevordering van eigen kracht; 2. werken aan sociale cohesie ten behoeve van het pedagogisch klimaat in de wijk; 3. het mobiliseren en/of vergroten van het sociaal netwerk van ouders, 4. signaleren van risico’s en ingrijpen waar nodig. Dit artikel gaat over de vraag hoe professionals die met ouders werken handen en voeten geven aan deze nieuwe werkwijze, welke ervaringen ze hierbij opdoen en welke dilemma’s ze tegenkomen. Deze vraag is onderzocht door professionals werkzaam in twee Centra voor Jeugd en Gezin in de stad Groningen te volgen in hun dagelijks werk. Daarbij is gebruik gemaakt van een methode die gericht is op het ontdekken van hun ervaringskennis. Deze methode bestaat uit het gericht observeren van professionals in hun dagelijks werken en uit het voeren van gesprekken hierover met professionals om hun overwegingen bij het handelen te achterhalen. Daaruit blijkt dat twee van de vier aspecten van preventief en omgevingsgericht werken sterker zijn ontwikkeld. CJG-professionals sluiten vaker aan bij de leefsituatie van ouders en pakken vaker risicosignalen op. Minder vaak maken ze gebruik van het sociale netwerk van ouders en werken ze aan sociale cohesie in de wijk. In het handelingsrepertoire lijken de preventieve aspecten sterker te zijn ontwikkeld dan de omgevingsgerichte. Professionals ervaren zowel morele, methodische als organisatorische dilemma’s bij preventief en omgevingsgericht werken.

The first fast-timing measurements from nuclides produced via the in-flight fission mechanism are reported. The lifetimes of the first 2+ states in 104,106Zr nuclei have been measured via β-delayed γ-ray timing of stopped radioactive isotope beams. An improved precision for the lifetime of the 21+ state in 104Zr was obtained, τ(21+)=2.90−20+25 ns, as well as a first measurement of the 21+ state in 106Zr, τ(21+)=2.60−15+20 ns, with corresponding reduced transition probabilities of B(E2;21+→0g.s.+)=0.39(2) e2b2 and 0.31(1) e2b2, respectively. Comparisons of the extracted ground-state deformations, β2=0.39(1) (104Zr) and β2=0.36(1) (106Zr) with model calculations indicate a persistence of prolate deformation. The data show that 104Zr is the most deformed of the neutron-rich Zr isotopes measured so far.

The isotope-production cross sections in p- and d-induced reactions on 93Zr at approximately 50 MeV/nucleon were measured by using the inverse-kinematics method at RIKEN RI Beam Factory. The measured data were compared with the previous experimental 93Zr + p, d at 105 and 209 MeV/nucleon data. This comparison represents that the isotopic distribution of production cross sections at 51 MeV p-induced reaction is appreciably different from those at 105 and 209 MeV. On the other hand, these three data sets show that the shape of isotopic distribution is similar in the case of the d-induced reaction. Also, the measured production cross sections were compared with the theoretical model calculations with Particle and Heavy Ion Transport code System (PHITS) version 3.10 in order to investigate the reproducibility of the models implemented in PHITS. The calculations well reproduced the experimental data even in such low incident energy, while several discrepancies were still seen as in the p- and d-induced reactions at 105 and 209 MeV/nucleon.

Spallation reaction for the long-lived fission product 107Pd has been studied for the purpose of nuclear waste transmutation. The isotopic-distribution cross sections on both proton and deuteron were obtained at 118 MeV/nucleon in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. A large cross-section difference was found between the proton and deuteron results for the light-mass products. The data were compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intranuclear cascade and evaporation processes. In addition, the potential of spallation reaction for transmutation of 107Pd is discussed.

Inelastic scattering cross sections to individual bound excited states of 104Sn were measured at 150 MeV/u beam energy and analyzed to evaluate the contribution of neutron and proton collectivity. State-of-the-art Quasi-Particle Random Phase Approximation (QRPA) with the D1M Gogny interaction reproduces the experimental proton collectivity and our inelastic scattering cross sections once used as input for a reaction calculation together with the Jeukenne–Lejeune–Mahaux (JLM) potentials. Experimental inelastic scattering cross section decreases by 40(24)% from 112Sn to 104Sn. The present work shows that (i) proton and neutron collectivities are proportional over a large range of tin isotopes (including 104Sn), as is typical for isoscalar excitations, and (ii) the neutron collectivity dominates. It suggests that the plateau in the mass range A=106–112 displayed by E2 transition probabilities is driven by neutron collectivity. Keywords: Collectivity, Inelastic scattering, Gamma spectroscopy

The decay of an isomeric state in the neutron-rich nucleus 129Cd has been observed via the detection of internal conversion and Compton electrons providing first experimental information on excited states in this nucleus. The isomer was populated in the projectile fission of a 238U beam at the Radioactive Isotope Beam Factory at RIKEN. From the measured yields of γ-rays and internal conversion electrons, a multipolarity of E3 was tentatively assigned to the isomeric transition. A half-life of T1/2=3.6(2) ms was determined for the new state which was assigned a spin of (21/2+), based on a comparison to shell model calculations performed using state-of-the-art realistic effective interactions. Keywords: Isomeric decays, Transition strengths, Shell model calculations

Active Heating-Distributed Temperature Sensing (AH-DTS) has the potential to allow for the measurement of groundwater flow velocities in situ. We placed DTS fiber-optic cables combined with a heating wire in direct contact with aquifer sediments in a laboratory scale groundwater flow simulator. Using this setup, we empirically determined the relationship between Δ T , the temperature difference by constant and uniform heating of the DTS cable and the background temperature of the groundwater system, and horizontal groundwater flow velocity. Second, we simulated the observed temperature response of the system using a plan-view heat transfer flow model to calibrate for the thermal properties of the sediment and to optimize cable setup for sensitivity to variation in groundwater flow velocities. Additionally, we derived an analytical solution based on the heat flow equation that can be used to explicitly calculate flow velocity from measured Δ T for this specific AH-DTS cable setup. We expect that this equation, after calibration for cable constitution, is valid for estimating groundwater flow velocity based on absolute temperature differences measured in field applications using this cable setup.

This article discusses the narratives of Dutch schoolchildren from varied cultural-ethnic backgrounds discussing experiences of being betrayed by a friend, and the lessons they learned from the experience. In line with earlier social constructivist research in western societies, the authors found that peers and friends acted as highly emotional forums for moral learning. Revealing intimate information led to awareness of two moral issues: the issue of norms of "true" friendship and the issue of the dilemma between conforming to group norms and asserting personal opinions. To develop a personal morality in the context of Dutch schools, the children needed trustworthy friends with whom to share intimate information in order to protect them from the peer group pressure to conform. Although both girls and boys constructed shared norms of real friendship and conformed to group norms to avoid being teased, disclosing intimate information seemed to evoke more emotional chaos in girls than it did in boys. (Contains 2 tables and 1 note.)

This article discusses a study of children's perspectives on disciplinary conflicts with their foster parents. Most children accept parental authority, but they also defend their personal autonomy and loyalties to peers. In this study, only birthchildren told real-life stories about fierce resistance to get their own way. Fierce resistance among foster children was motivated by inner conflicts and confusion. Obedience among foster children often derived from fear of punishment or a feeling of impotence. The authors discuss the theoretical and pedagogical implications of these findings.

The neutron-rich nuclei 136Sn and 132Cd have been studied in the purpose of nuclear structure for the nuclei beyond the doubly-magic nucleus 132Sn. The 2+1 → 0+ gs transitions were identified for these two nuclei using in-beam γ-ray spectroscopy in coincidence with one- and two-proton removal reactions, respectively, at the RIKEN Radioactive Isotope Beam Factory. The 2+ 1 state in 136Sn is found to be similar to that for 134Sn indicating the seniority scheme may also hold for the heavy tin isotopes beyond N = 82. For 132Cd, the 2+ 1 state provides the first spectroscopic information in the even-even nuclei locating in the region “southeast” of 132Sn and the result is discussed in terms of proton-neutron configuration mixing. In both these two nuclei, it was found that the valence neutrons play an essential role in their low-lying excitations.

The region of neutron-rich nuclei above the N = 50 magic neutron shell closure encompasses a rich variety of nuclear structure, especially shapeevolutionary phenomena. This can be attributed to the complexity of sub-shell closures, their appearance and disappearance in the region, such as the N = 56 sub shell or Z = 40 for protons. Structural effects reach from a shape phase transition in the Zr isotopes, over shape coexistence between spherical, prolate, and oblate shapes, to possibly rigid triaxial deformation. Recent experiments in this region and their main physics viewpoints are summarized.

This contribution will report on the experimental work on the level structure of 168Dy. The experimental data have been taken as part of the EURICA decay spectroscopy campaign at RIBF, RIKEN in November 2014. In the experiment, a 238U primary beam is accelerated up to 345 MeV/u with an average intensity of 12 pnA. The nuclei of interest are produced by in-flight fission of 238U impinging on Be target with a thickness of 5 mm. The excited states of 168Dy have been populated through the decay from a newly identified isomeric state and via the β decay from 168Tb. In this contribution, scientific motivations, experimental procedure and some preliminary results for this study are presented.

Isotopic production cross sections were measured for proton- and deuteron-induced reactions on 93Nb by means of the inverse kinematics method at RIKEN Radioactive Isotope Beam Factory. The measured production cross sections of residual nuclei in the reaction 93Nb + p at 113 MeV/u were compared with previous data measured by the conventional activation method in the proton energy range between 46 and 249 MeV. The present inverse kinematics data of four reaction products (90Mo, 90Nb, 88Y, and 86Y) were in good agreement with the data of activation measurement. Also, the model calculations with PHITS describing the intra-nuclear cascade and evaporation processes generally well reproduced the measured isotopic production cross sections.

Isotopic production cross sections in the proton- and deuteron-induced spallation reactions on 93Zr at an energy of 105 MeV/u were measured in inverse kinematics conditions for the development of realistic nuclear transmutation processes for long-lived fission products (LLFPs) with neutron and light-ion beams. The experimental results were compared to the PHITS calculations describing the intra-nuclear cascade and evaporation processes. Although an overall agreement was obtained, a large overestimation of the production cross sections for the removal of a few nucleons was seen. A clear shell effect associated with the neutron magic number N = 50 was observed in the measured isotopic production yields of Zr and Y isotopes, which can be reproduced reasonably by the PHITS calculation.

This short paper presents the identification of a metastable, isomeric-state decay in the neutron-rich odd-odd, prolate-deformed nucleus 166Tb. The nucleus of interest was formed using the in-flight fission of a 345 MeV per nucleon 238U primary beam at the RIBF facility, RIKEN, Japan. Gamma-ray transitions decaying from the observed isomeric states in 166Tb were identified using the EURICA gamma-ray spectrometer, positioned at the final focus of the BigRIPS fragments separator. The current work identifies a single discrete gamma-ray transition of energy 119 keV which de-excites an isomeric state in 166Tb with a measured half-life of 3.5(4) μs. The multipolarity assignment for this transition is an electric dipole and is made on the basis internal conversion and decay lifetime arguments. Possible two quasi-particle Nilsson configurations for the initial and final states which are linked by this transition in 166Tb are made on the basis of comparison with Blocked BCS Nilsson calculations, with the predicted ground state configuration for this nucleus arising from the coupling of the v(1-/2)[521] and π(3+/2) Nilsson orbitals.

Spallation reactions for the long-lived fission products 137Cs, 90Sr and 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. and the cross-section differences between the proton and deuteron are found to be larger for lighter fragments. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intra-nuclear cascade and evaporation processes.