Models for Rotating Nuclei  Cranking and Rotor + Particles Coupling
(2007) Abstract
 This dissertation investigates properties of rotating atomic nuclei. Studies are performed using the cranking model and in the particles + rotor model. Properties studied are energy spectra and electromagnetic transition probabilities. The thesis also investigates the use of different liquid drop models at high spin values and
studies the use of the particle + rotor approximation for the description of different 'exotic' ways of rotating.
The dissertation comprises six original papers, which are presented following an introduction to the fields of research and the methods used and the systems studied.
Paper I investigates the use of different meanfield parameters for the description of experimental highspin... (More)  This dissertation investigates properties of rotating atomic nuclei. Studies are performed using the cranking model and in the particles + rotor model. Properties studied are energy spectra and electromagnetic transition probabilities. The thesis also investigates the use of different liquid drop models at high spin values and
studies the use of the particle + rotor approximation for the description of different 'exotic' ways of rotating.
The dissertation comprises six original papers, which are presented following an introduction to the fields of research and the methods used and the systems studied.
Paper I investigates the use of different meanfield parameters for the description of experimental highspin states in 86Nb. A better agreement with experimental data could be found, however some experimental features proved hard to explain.
In Paper II new experimental data on highspin states in 58Ni was presented and compared with cranking calculations. A good agreement with calculation led to a clear interpretation of all observed states. The interaction and transitions between two of the rotational
bands are analyzed and found to be sensitive to the deformation of the nucleus.
In Paper III the average pairing energy is removed from the parameters of the liquiddrop model by performing a refitt to nuclear groundstate masses. The modified model is then used to calculate the total energy of the nucleus at highspin values. Two different models are compared and one is found to be more reliable for light nuclei.
In Paper IV the usual particle plus rotor model is extended to incorporate an arbitrary number of particles coupled to the rotor. This model is then used to describe the so called shears bands where states are formed by the coupling of perpendicular neutron and proton
spin vectors. The same model is employed in Paper V for the description of collective wobbling excitations in nuclei.
In Paper VI, new experimental data on quadrupole transitions in 142Gd are presented. These data are compared to the result of cranking calculations employing a monopole pairing interaction. Based on the calculations the relatively small transition probabilities are interpreted as being the result of the rotation
taking place around the longest principal axis of the mass
distribution. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/record/618465
 author
 Carlsson, Gillis ^{LU}
 supervisor

 Ingemar Ragnarsson ^{LU}
 Sven Åberg ^{LU}
 Ragnar Bengtsson ^{LU}
 opponent

 Professor Pomorski, Krzysztof, Katedra Fizyski Teoretycznej, Uniwersytet Marii CurieSklodowskiej, Lublin, Poland
 organization
 publishing date
 2007
 type
 Thesis
 publication status
 published
 subject
 keywords
 highspin masses, 58Ni, particle + rotor model, 86Nb, 163Lu, wobbling, cranking
 pages
 130 pages
 defense location
 Lecture hall F, Fysikum, Sölvegatan 14A, Lund University Faculty of Engineering
 defense date
 20071214 13:30
 ISBN
 9789162873554
 language
 English
 LU publication?
 yes
 id
 c2823afd79e449d1a37a32b485c7170d (old id 618465)
 date added to LUP
 20071122 11:59:25
 date last changed
 20160919 08:45:19
@phdthesis{c2823afd79e449d1a37a32b485c7170d, abstract = {This dissertation investigates properties of rotating atomic nuclei. Studies are performed using the cranking model and in the particles + rotor model. Properties studied are energy spectra and electromagnetic transition probabilities. The thesis also investigates the use of different liquid drop models at high spin values and<br/><br> studies the use of the particle + rotor approximation for the description of different 'exotic' ways of rotating. <br/><br> The dissertation comprises six original papers, which are presented following an introduction to the fields of research and the methods used and the systems studied.<br/><br> Paper I investigates the use of different meanfield parameters for the description of experimental highspin states in 86Nb. A better agreement with experimental data could be found, however some experimental features proved hard to explain. <br/><br> In Paper II new experimental data on highspin states in 58Ni was presented and compared with cranking calculations. A good agreement with calculation led to a clear interpretation of all observed states. The interaction and transitions between two of the rotational<br/><br> bands are analyzed and found to be sensitive to the deformation of the nucleus.<br/><br> In Paper III the average pairing energy is removed from the parameters of the liquiddrop model by performing a refitt to nuclear groundstate masses. The modified model is then used to calculate the total energy of the nucleus at highspin values. Two different models are compared and one is found to be more reliable for light nuclei.<br/><br> In Paper IV the usual particle plus rotor model is extended to incorporate an arbitrary number of particles coupled to the rotor. This model is then used to describe the so called shears bands where states are formed by the coupling of perpendicular neutron and proton<br/><br> spin vectors. The same model is employed in Paper V for the description of collective wobbling excitations in nuclei. <br/><br> In Paper VI, new experimental data on quadrupole transitions in 142Gd are presented. These data are compared to the result of cranking calculations employing a monopole pairing interaction. Based on the calculations the relatively small transition probabilities are interpreted as being the result of the rotation<br/><br> taking place around the longest principal axis of the mass <br/><br> distribution.}, author = {Carlsson, Gillis}, isbn = {9789162873554}, keyword = {highspin masses,58Ni,particle + rotor model,86Nb,163Lu,wobbling,cranking}, language = {eng}, pages = {130}, school = {Lund University}, title = {Models for Rotating Nuclei  Cranking and Rotor + Particles Coupling}, year = {2007}, }