Search for neutrinoless double beta decay of Cd-116 with the NEMO-3 experiment

This dissertation describes the approach taken in measuring two neutrino double beta decay of Cd-116 to the ground state of Sn-116 and in searching for the effective Majorana neutrino mass by placing a lower limit on the half-life for neutrinoless double beta decay of Cd-116 using the powerful technique of a combined tracking chamber and calorimeter with the NEMO-3 detector. The description of the detector, its natural background contamination, and the tools used to perform the analysis are discussed. The single electron channel was used to identify source foil contamination from [beta]-emitters and the electron-gamma channel was used to confirm the previous measurements of Tl-208 and Bi-214 contaminations in the source foil. Using these backgrounds, the two neutrino double beta decay half-life of Cd-116 was measured for the single states dominance hypothesis and the higher states dominance hypothesis. The final data set was defined to be data from Phrase One and Phase Two for the medium and low activity regions. Using 1471 days of data, the values of the half-life for the single data dominance hypothesis and the higher states dominance hypothesis were found.