My thesis project was carried out in the field of experimental nuclear and particle physics. The idea is to exploit a rare nuclear decay mode in order to learn more about properties of neutrinos, in particular their unknown mass scale and particle nature. This is made possible by participating in the COBRA project. The aim of the COBRA experiment is to search for neutrinoless double beta decay (0νββ-decay) as a probe to new physics beyond the standard model. It should assist in finding a value for the mass of the neutrino as well as it’s type, i.e. whether it is a Dirac or Majorana particle.

Warwick’s initial involvement was the design and investigation of the shielding. For rare event experiments, such as COBRA, influences from background sources need to be kept a minimum so as not to ”drown-out” the expected peak in the energy spectrum, signifying the neutrinoless double beta decay mode. The aim of my thesis was to work towards designing and developing a low background environment as well as optimising and simplifying as far as possible the way in which the COBRA experiment could be operated. The thesis does not aim to form a fully comprehensive final COBRA experiment but merely to contribute as far as possible to the process of reaching the end product.