Sökning: "Fission"
Visar resultat 1 - 5 av 170 avhandlingar innehållade ordet Fission.
1. To fission or not to fission: 230Ac
Sammanfattning : Around half of the elements heavier than iron found in the Universe are believed to have been formed during the rapid neutron capture process (r-process). During the r-process, very neutron-rich nuclei are created through a series of neutron captures and β−-decay reactions. LÄS MER
2. Isomeric yield ratios in nuclear fission
Sammanfattning : Isomeric yield ratios (IYR), referring to the relative yield of the high spin states of a nucleus to the total yield of all observed states, is an observable of nuclear fission that has the potential to improve our understanding of the fission dynamics. Apart from that, systematic observations of IYRs can also contribute to other areas, such as the validation of fission models, modelling of the r-process in stellar nucleosynthesis, studies of the antineutrino mixing angle, the safety of present-day nuclear reactors, and the design of advanced reactor systems. LÄS MER
3. The neutron-induced fission cross section of 233Pa : and the quest for clean and safe nuclear energy
Sammanfattning : Neutron-induced fission of 233Pa has been investigated between 1.0 and 8.5 MeV, and the reaction cross section was determined. Due to the short half-life of 233Pa for β-decay, fission events from the daughter product 233U affect the analysis of the protactinium experiment. LÄS MER
4. Nuclear fission and fusion in a random-walk model
Sammanfattning : This dissertation deals with theoretical descriptions of nuclear fission and synthesis of superheavy elements via fusion. The associated shape evolutions are treated using a random-walk approach where both the potential energy and the nuclear level density influence the dynamics. LÄS MER
5. Isomeric yield ratio measurements with JYFLTRAP : In quest of the angular momentum of the primary fragments
Sammanfattning : In this thesis, isomeric yield ratios of twenty nuclides produced in the fission of natU and 232Th by protons at 25-MeV and natU by high-energy neutrons were studied. The experiments were performed at the IGISOL-JYFLTRAP facility at the University of Jyväskylä. LÄS MER
