Develop channel selection techniques in octupole deformed nuclei

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There have been a number of models developed for atomic nuclei which work particularly well for stable or near stable nuclei. However, it is important that we investigate if these models are true for the far from stable nuclei, known as exotic nuclei. These exotic nuclei are ones which have a large imbalance in the number of protons and neutrons present, such nuclei will be the ones of interest in this PhD project. When nuclei are in the excited states they usually emit gamma rays. If the properties of these gamma rays are measured then they can be used to determine certain properties of nuclei, such as their shapes. Gamma ray spectroscopy is one of the most efficient ways to determine properties of nuclei as gamma rays are a highly penetrating form of radiation and can be detected with good efficiency and a high energy resolution when using semiconductor germanium detectors. If there are a large number of these detectors used then multiple gamma rays can be detected at the same time and a technique called gamma ray coincidence spectroscopy can be used. There are some facilities in which this can be done, such as Jurogamll at JYFL in Finland and Gammasphere in Chicago, where a large array of semiconductor detectors has been constructed. These are two of the facilities in which experiments will be conducted throughout this PhD project. The nuclei that we are interested in are often produced in reactions with very small production probability. This means that there is a challenge to develop channel selection techniques in which these weakly produced nuclei can be selected from a background of the more strongly populated nuclei. The nuclei that will be of special interest in this PhD project are the octupole deformed nuclei, also known as "pear shaped" nuclei. One nucleus that is suspected to have this shape is the 116Ba nucleus. There is an experiment scheduled in the Legnaro National Laboratory in Italy to study this exotic 116Ba nucleus and part of the PhD project would involve helping to run that experiment and to analyse the data. This experiment will involve using the new Galileo gamma ray spectrometer along with Euclides charged particle detector and the Neutron Wall array of neutron detectors. When this analysis is complete there will be following experiments that will be carried out in the other laboratories.