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Theoretical calculations of γ-ray feeding patterns for Gd, Dy and Er nuclei

The side-feeding patterns and the spectra of unresolved γ-lines are calculated for Gd, Dy and Er nuclei with neutron numbers from 82 to 86. Energies and configurations for states from the yrast line and approximately 2 MeV higher in energy are calculated as many-quasiparticle configurations in a deformed oblate potential. The γ-cascade is simulated by a Monte Carlo calculation. With a common avera

Microscopic description of a low-lying Kπ = 1+ mode in 156Gd

A recently observed Kπ = 1+ mode in deformed nuclei is studied microscopically. By calculating the energies, the B(M1)-values and the form-factors of inelastic electron scattering for 156Gd, we conclude that the relatively strong M1-strength observed at 3.075 MeV comes predominantly from the convection current of proton excitations in the Oh 1 2-orbit. We suggest a search for the M1-strength aroun

Deformation changes along the yrast line in 160Yb

The yrast states of 160Yb are calculated using the cranked HFB model with particle-number projection and assuming diabatic bands. The energy of each state is minimized with respect to the proton and neutron pairing gap parameters and the deformation parameters ε and γ. The deformation of the ground band is found to increase with increasing spin, i.e. ε gets larger. Simultaneously γ gets slightly n

On the expansion of integrals containing Fermi distributions

We derive an expansion of integrals containing a general function multiplied by a Fermi function raised to an arbitrary power v. When v is an integer, direct expressions for the expansion coefficients are given. The expansion is found to converge quite rapidly if the diffuseness of the Fermi distribution is small, and when v ≳ 1.

Shape coexistence and high-spin states in 28Si

The spectrum of 28Si is investigated within the cranked Nilsson-Strutinsky model with all kinds of many-particle-many-hole excitations accounted for. Calculated excitation energies and quadropole moments are compared with experimental data. The recently observed backbend from 8+ to 10+ is suggested to be caused by the crossing of the oblate ground band with a prolate or slightly triaxial band havi

A microscopic analysis of moments of inertia

A microscopic analysis of moments of inertia is performed within the cranked Nilsson model. Special emphasis is put on the second-derivative moment of inertia, J(2). Contributions to this from changes of rotational frequency and deformation are separately discussed. A simple expression for the latter is derived and it is for a studied series of Yb isotopes usually found to contribute with less tha

A unified approach to particle-holes and rotations in the spectrum of 16O

The cranked Nilsson-Strutinsky formalism is applied to the many-faceted spectrum of 16O. The deformation parameters ε{lunate}, γ and ε4 are varied independently and many-particle-many-hole excitations are considered in the rotating system. Potential-energy surfaces are presented at different values of spin, parity and signature. Surprisingly good agreement is obtained when the different minima are

On the analogy between backbending in gauge space and in ordinary space

The interplay between angular momentum and particle number (which is the equivalent to the angular momentum in gauge space) is studied. The same technique that is used in the case of rotations in ordinary space can be used in gauge space for investigating the properties of individual quasiparticle levels and the total angular momentum of a nucleus. We study the isotopes of Dy and W, where a back-

A new formalism for high spin states applied to the sd-shell region

A new development within the high spin Nilsson-Strutinsky formalism presented and applied to certain sd-shell nuclei. The previous method of calculating potential-energy surfaces as a function of angular momentum using interpolated spin values is not satisfactory when studying the individual bands for these light nuclei. In the present research, manyparticle many-hole excitations are considered in

Application of the cranked Nilsson model in some light nuclei : The super backbend in 11B and 11C?

The Nilsson model of high-spin states is developed to include particle-hole excitations for rotation around an arbitrary axis. Potential-energy surfaces are calculated with constraints not only on the total spin but also on parity and signature. The method is applied to very light nuclei with A ~ 10. Good agreement for the ground-state bands of 8Be and 12C is obtained and predictions are made for

Some properties of superdeformed nuclei

Nuclear superdeformation is studied theoretically using both simple models and more realistic numerical calculations. From the simple models general rules are formulated about the shell structure of the nucleus at large deformation, its affinity for reflection asymmetric or necked-in distortions and its response to rotation. The numerical calculations are based on realistic single-particle schemes

Survey of collective and single-particle features in the yrast domain of the A~50 nuclei

Collective properties at low and high spin for nuclei with Z ≥ 64 and N ≥ 82 are calculated on the basis o f deformed single-particle potentials. The calculations are confronted with the available experimental data like low-lying octupole bands, rotational bands of transitional nuclei with N ≥ 90 and evidence for collectivity in high-spin single-particle spectra. In the latter collective triaxiali

Nilsson-Strutinsky model of very high spin states

The Nilsson-Strutinsky approach to the description of yrast properties at very high spins is reviewed. Some recent calculations are presented and discussed with regard to the available experimental data. A nice agreement in the Te-region is pointed out. The aim is however more to describe physical trends than to make detailed predictions for specific nuclei. The general variation of the shell effe

Superheavy elements at high angular momenta

Potential-energy surfaces at high spin are calculated for nuclei in the superheavy region by use of the cranked Nilsson hamiltonian. It is found, that the maximum fission barrier is shifted from the doubly magic 298114 to nuclei with fewer protons and more neutrons, as the spin increases. We also estimate, by use of simple models, the half-lives associated with alpha-decay, gamma-decay and fission

Yrast properties in the A ∼ 40-80 region

Calculations with the cranking-plus-Strutinsky formalism indicate that some part of the yrast line in almost all the nuclei of the A ∼ 40-80 region may be of non-collective type, corresponding to rotation around a symmetry axis. A numerical study of many such single-particle spectra shows that even at very high spins there is a non-negligible probability for the occurrence of isomers. This conclus

An investigation of yrast traps in some prolate Hf isotopes

The cranked modified oscillator potential is used to study the nuclei 172-18072Hf at very high angular momenta. All these isotopes are found to "rotate around the prolate symmetry axis" for spin values I= 15-40 h {combining short stroke overlay}. In this region of spin we then look for prolate yrast traps. The pairing interaction with an approximative particle number projection as well as the hexa

The Unclear Role of Strategic Communicators : Professionalization Through Reflexivity on Action

The strategic role of communication practitioners has been discussedsince the 1970s. While it might not be surprising that managers andcoworkers view their roles as unclear, it is more surprising that commu-nication practitioners themselves also struggle with explaining theirstrategic roles and the value of their work. To elucidate the strategicwork of communication practitioners, we conducted a s

Eliter och elitisering i civilsamhället

Civilsamhälleseliter kan definieras som individer med en ledande position i civilsamhällesorganisationer som ansamlar och förfogar över en oproportionerlig stor mängd resurser. På så vis har de bäst förutsättningar att utöva makt och inflytande i samhället

Aesthetic Dimensions of Literary Studies : Multimodality and Creative Learning

In Sweden, the occurrence of fictional texts in various media formats, including TV series, films, and computer games, most of which are in English, is constantly growing. In an increasingly digitalised society, there is a need for teaching that understands and meets the demand for aesthetic values as well as multimodality and creativity. Highlighting the aesthetic dimension of literary studies, t

Från finrummet till vardagsrummet : Transmedialt berättande som litteraturdidaktisk underhållning

This study explores re-creation processes, through transmedia storytelling, that are made visible in the Swedish TV-programme Helt lyriskt (2018), where music artists transmediate Swedish poems into songs. The aim is to analyse, through a close-reading method, two episodes of Helt lyriskt in order to discuss how processes of transmedia storytelling make literary analyses visible and accessible to