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The electromagnetic character of the ΔI=1 transitions connecting the 1- to 0-phonon and the 2- to 1-phonon wobbling bands should be dominated by an E2 component, due to the collective motion of the entire nuclear charge. In the present work it is shown, based on combined angular correlation and linear polarization measurements, that the mixing ratios of all analyzed connecting transitions between low-lying bands in $^{135}$Pr interpreted as 0-, 1-, and 2-phonon wobbling bands, have absolute values smaller than one. This indicates predominant M1 magnetic character, which is incompatible with the proposed wobbling nature. All experimental observables are instead in good agreement with quasiparticle-plus-triaxial-rotor model calculations, which describe the bands as resulting from a rapid re-alignment of the total angular momentum from the short to the intermediate nuclear axis.

The nature of two high-spin bands in 136Nd built on the two-quasiparticle configuration πh211/2, predicted by the triaxial projected shell model as good candidates of transverse wobbling bands, are investigated experimentally. The mixing ratio of one ΔI=1 transition connecting the one-phonon and the zero-phonon wobbling bands is established from a high-statistics JuroGam II γ-ray spectroscopy experiment by using the combined angular correlation and linear polarization method. The resulting wobbling excitation energy and ratios of reduced electromagnetic transition probabilities are in good agreement with results of a new particle-rotor model which rigidly couples the total angular momentum of two quasiparticles to a triaxial core in an orthogonal geometry, confirming thus the transverse wobbling nature of the bands. peerReviewed

International audience; Two new excited bands built on the πh11/2 configuration have been identified in Nd135 in addition to the known πh11/2 band. The energy spectra of the excited bands and the available electromagnetic transition probabilities are in good agreement with theoretical results obtained using quasiparticle-plus-triaxial-rotor model calculations. The properties of the bands identify them as tilted precession bands instead of wobbling bands. Our results give a new insight into the interpretation of the low-lying bands in odd-A mass nuclei, and can stimulate future studies to address the nuclear triaxiality.

Two new excited bands built on the πh11/2 configuration have been identified in ¹³⁵Nd in addition to the known πh11/2 band. The energy spectra of the excited bands and the available electromagnetic transition probabilities are in good agreement with theoretical results obtained using quasiparticle-plus-triaxial-rotor model calculations. The properties of the bands identify them as tilted precession bands instead of wobbling bands. Our results give a new insight into the interpretation of the low-lying bands in odd-A mass nuclei, and can stimulate future studies to address the nuclear triaxiality.

Government net worth – total assets less liabilities – has declined considerably relative to national income in a number of OECD countries in recent decades, including the United States, the United Kingdom, Japan and Germany. Notably, however, in thinking about the links between fiscal policy and bond markets, the focus of policy and academic debates has tended to be on the liabilities side of the government balance sheet. Typically, not much attention has been paid to the extent to which any increase in government debt is accompanied by government asset accumulation and hence affects government net worth. Using novel data on both sides of the government balance sheet both for a panel of OECD countries in recent decades and for the United States over the long term, we provide panel data and time series-based evidence that for bond markets, not all government debt is created equal: for explaining government borrowing cost empirically, (i) government assets are significant in addition to government liabilities, and (ii) it is government net worth rather than government liabilities that matters when both are included. The central country-specific fiscal factor driving bond yields hence appears to be government net worth.

Experimental signatures of moderately enhanced octupole correlations at high spin in ¹³⁶Nd are indicated for the first time. The extracted dipole moments of two negative-parity bands are only two times smaller than those of the lanthanide nuclei with N≈90 which present well-established octupole correlations. Calculations using the cranked quasiparticle random phase approximation and a model of quadrupole-octupole rotations with octupole vibrations reveal the structure of the bands and the enhanced octupole correlations at high spin in ¹³⁶Nd.

Several new bands have been identified in $^{130}$Ba, among which there is one with band-head spin 8+. Its properties are in agreement with the Fermi-aligned νh11/22, 7/2−[523]⊗9/2−[514] Nilsson configuration. This is the first observation of a two-quasiparticle t-band in the A=130 mass region. The t-band is fed by a dipole band involving two additional h11/2 protons. The odd-spin partners of the proton and neutron S-bands and the ground-state band at high spins are also newly identified. The observed bands are discussed using several theoretical models, total Routhians surfaces (TRS), tilted axis cranking (TAC), particle rotor model (PRM) and projected shell model (PSM), which strongly suggest the coexistence of prolate and oblate shapes polarized by rotation aligned two-proton and two-neutron configurations, as well as prolate collective rotations around axes with different orientations. With the new results, $^{130}$Ba presents one of the best and most complete sets of collective excitations that a γ-soft nucleus can manifest at medium and high spins, revealing a diversity of shapes and rotations for the nuclei in the A=130 mass region.

One new pair of positive-parity chiral doublet bands have been identified in the odd-A nucleus 135Nd which together with the previously reported negative-parity chiral doublet bands constitute a third case of multiple chiral doublet (MχD) bands in the A≈130 mass region. The properties of the MχD bands are well reproduced by constrained covariant density functional theory and particle rotor model calculations. The newly observed MχD bands in 135Nd represents an important milestone in supporting the existence of MχD in nuclei.

One new pair of positive-parity chiral doublet bands have been identified in the odd-A nucleus 135Nd which together with the previously reported negative-parity chiral doublet bands constitute a third case of multiple chiral doublet (MχD) bands in the A ≈ 130 mass region. The properties of the MχD bands are well reproduced by constrained covariant density functional theory and particle rotor model calculations. The newly observed MχD bands in 135Nd represents an important milestone in supporting the existence of MχD in nuclei. peerReviewed

Both government net worth – the balance of government assets and liabilities – and government investment have fallen substantially, relative to national income, in many OECD countries in recent decades (Atkinson, 2015; IMF, 2014). This thesis investigates the macroeconomic implications of these developments, for fiscal sustainability on the one hand and for economic growth on the other. Chapter 1 explores the relevance of the composition of government budget deficits for government bond markets. We use data for 31 OECD countries from 1990 to 2014 from the European Commission's AMECO database to show that, from the perspective of bond markets, not all budget deficits are created equal: markets charge significantly higher interest rates for deficits due to government current spending than for those due to government investment. Chapter 2 investigates whether bond markets accord importance to the asset side of the government balance sheet and hence to government net worth, above and beyond government liabilities. We use data on both sides of the government balance sheet drawn from Piketty and Zucman (2014) – for a panel of 10 OECD countries in recent decades and for the United States over the long term – to show that, for bond markets, not all government debt is created equal: for explaining the cost of government borrowing empirically, government assets are significant, and it is government net worth rather than government liabilities that matters. Chapter 3 is concerned with how government asset accumulation affects economic growth. We first assess the predictive relevance of government investment and government consumption for future growth, and then estimate a standard growth model in the spirit of Solow (1956) using econometric methods suitable for addressing possible endogeneity. We find that there is a significant difference in the growth effects of government investment and government consumption: government investment aids growth, while government consumption significantly impedes growth, both for a set of OECD countries and globally. These findings help to rationalise why bond markets take into account the extent to which a government budget deficit or debt increase is accompanied by government asset accumulation, as we found in Chapters 1 and 2. They also imply that the composition of government budget deficits and government balance sheets will impact future growth prospects and matter for the implementation of austerity policies and the design of fiscal rules in monetary unions.

International audience; Lifetimes of several short-lived excited states in Nd138 were measured with the ROSPHERE array at IFIN-HH, Bucharest, using the recoil-distance Doppler shift technique following the Sb123(F19,4n) reaction. The resulting electromagnetic transition probabilities are compared to large-scale shell model calculations and to constrained Hartree-Fock-Bogoliubov calculations with the Gogny D1S interaction, configuration mixing, and a five-dimensional collective Hamiltonian formalism. The onset of collectivity in Nd isotopes below the N=82 shell closure and the deformation induced by the alignment of protons and neutron holes in the h11/2 orbitals are discussed.

International audience; The g factor of the 56 ns half-life isomeric state in $^{128}$Cs has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g=+0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in $^{128}$Cs demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.

The level structure of ¹³⁶Nd has been investigated using the ¹⁰⁰Mo(⁴⁰Ar, 4n) reaction and the JUROGAM II+RITU+GREAT setup. The level scheme has been extended significantly. Many new bands have been identified both at low and high spin, among which are five nearly degenerate bands interpreted as chiral partners. Excitation energies, spins, and parities of the previously known bands are revised and firmly established, and some previously known bands have been revised. Configurations are assigned to the observed bands based on cranked Nilsson-Strutinsky calculations. The band structure of ¹³⁶Nd is now clarified and the various types of single-particle and collective excitations are well understood.

20 pags., 12 figs., 14 tabs., A Coulomb-excitation experiment to study electromagnetic properties of Ca42 was performed using a 170-MeV calcium beam from the TANDEM XPU facility at INFN Laboratori Nazionali di Legnaro. γ rays from excited states in Ca42 were measured with the AGATA spectrometer. The magnitudes and relative signs of ten E2 matrix elements coupling six low-lying states in Ca42, including the diagonal E2 matrix elements of 21+ and 22+ states, were determined using the least-squares code gosia. The obtained set of reduced E2 matrix elements was analyzed using the quadrupole sum rule method and yielded overall quadrupole deformation for 01,2+ and 21,2+ states, as well as triaxiality for 01,2+ states, establishing the coexistence of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in Ca42. The experimental results were compared with the state-of-the-art large-scale shell-model and beyond-mean-field calculations, which reproduce well the general picture of shape coexistence in Ca42., K.H.-K. acknowledges support from the Research Council of Norway under Grant No. 213442. T.R.R. acknowledges computing time at GSI-Darmstadt and support from Spanish MINECO under Programa Ramon y Cajal 11420 and FIS-2014-53434-P (T.R.R.). We also acknowledge the support by Generalitat Valenciana, Spain, under Grant No. PROMETEOII/2014/019 and by the FEDER funds of the European Commission (A. Gadea), Spanish Ministerio de Economía y Competitividad under contract FPA2014-57196-C5 (A. Jungclaus, A Gadea), German Bundesministerium für Bildung und Forschung (BMBF) under Contract No. 05P12PKFNE TP4 (B. Birkenbach), the Polish National Science Centre under Projects No. 2011/03/B/ST2/01894, No. DEC-2013/10/M/ST2/00427, No. 2013/08/M/ST2/00591, No. UMO-2014/14/M/ST2/00738 (COPIN-INFN Collaboration), No. 2015/17/B/ST2/01534, No. 2016/22/M/ST200269, the UK STFC under Grants No. ST/J000124/1 and No. ST/L005735/1. The EAGLE Collaboration thanks the European Gamma-Ray Spectroscopy Pool (GAMMAPOOL) for the loan of Ge detectors.

The level structure of 136Nd has been investigated using the 100Mo(40Ar, 4n) reaction and the JUROGAM II+RITU+GREAT setup. The level scheme has been extended significantly. Many new bands have been identified both at low and high spin, among which are five nearly degenerate bands interpreted as chiral partners. Excitation energies, spins, and parities of the previously known bands are revised and firmly established, and some previously known bands have been revised. Configurations are assigned to the observed bands based on cranked Nilsson-Strutinsky calculations. The band structure of 136Nd is now clarified and the various types of single-particle and collective excitations are well understood. peerReviewed

WOS: 000423131200005, PubMed: 29376727, The g factor of the 56 ns half-life isomeric state in Cs-128 has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g = +0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in Cs-128 demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin., Polish National Science Centre (NCN) [2013/10/M/ST2/00427]; Polish-French Collaboration [COPIN-IN2P3 (06-121)]; Chinese Major State 973 Program [2013CB834400]; National Natural Science Foundation of China [11335002, 11375015, 11461141002, 11621131001]; China Postdoctoral Science Foundation [2015M580007, 2016T90007]; U.S. Department of Energy (DOE), Office of Science, Office of Nuclear Physics [DE-AC02-06CH11357]; U.S. National Science Foundation [1713857], The authors wish to thank the ORSAY Tandem team for providing an excellent and stable beam. This project was supported in part by Polish National Science Centre (NCN) Grant No. 2013/10/M/ST2/00427. This work was partially supported by the Polish-French Collaboration No. COPIN-IN2P3 (06-121). This work was partly supported by the Chinese Major State 973 Program No. 2013CB834400, the National Natural Science Foundation of China (Grants No. 11335002, No. 11375015, No. 11461141002, and No. 11621131001), and the China Postdoctoral Science Foundation under Grants No. 2015M580007 and No. 2016T90007. This work was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357 (P.W.Z.). This work was partly supported by the U.S. National Science Foundation, Grant No. 1713857.

The structure of neutron-rich 96,98Sr nuclei was investigated by low-energy safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility, CERN, with the MINIBALL spectrometer. A rich set of transitional and diagonal E2 matrix elements, including those for non-yrast structures, has been extracted from the differential Coulomb-excitation cross sections. The results support the scenario of a shape transition at N=60, giving rise to the coexistence of a highly deformed prolate and a spherical configuration in 98Sr, and are compared to predictions from several theoretical calculations. The experimental data suggest a significant contribution of the triaxal degree of freedom in the ground state of both isotopes. In addition, experimental information on low-lying states in 98Rb has been obtained. ispartof: Physical Review C vol:94 issue:5 status: published