Neutron-induced fission fragment angular distribution at cern n_tofthe th-232 case

Resumo

The proposed research task for this thesis work is focused on the study of the fission mechanisms induced by high-energy neutrons, between a few MeV up to more than 1 GeV. Presently available data in the nuclear databases (ENDF, JENDL,...) exhibit a lack of information in this energy range, so that the international agencies, as the OCDE-NEA and the IAEA have been made a series of recommendations on the need of the most relevant data that should be measured. Nuclear fission is an extremely complex process where the collective behaviour of the nucleons inside a highly deformed nucleus leads to the nuclear rupture in two lighter fragments, of comparable masses, that are called "fission fragments" (FF). These FF are produced with a certain mass distribution, in function of the energy of the collision, and exhibiting also a certain angular distribution of those FF. The study of the fission cross sections and of the angular distributions of the fragments are very important parameters for the development of stellar nucleo-synthesis models, for the calculations on the fuel in fast nuclear reactors, as well as for the transmutation of high-radioactive nuclear waste. The work will be developed in the Grupo Experimental de Núcleos y Partículas (GENP), having a long experience in this kind of tasks, and inside international collaborations with projects of several international institutions, as the CERN (Geneve, Switzerland), GSI-FAIR (Darmstadt, Germany) and IPNO (Orsay, France). The work will consist on the development of the needed experimental equipment, on the installation in the laboratories of the mentioned accelerators and on the analysis of the obtained data. This work will give to the PhD student a whole training in all the experimental Physics field, favouring his capacity of integration in multidisciplinary international teams, by programmed stays in the laboratories mentioned above.