Measurement of Theta-13 Neutrino Mixing Angle from the Disappearance of Electron Antineutrinos at the Double Chooz Experiment

The measurement of the remaining neutrino-mixing angle, theta-130, is a critical step toward further understanding of neutrino properties and to guide future neutrino oscillation experiments. Double Chooz has a unique opportunity to perform this measurement building on the original CHOOZ reactor anti-neutrino experiment, the experience that set the previous limits on theta-13. In the first phase of Double Chooz, 101 days of data was analyzed with only the far detector operating of a two-detector plan. In this thesis I will describe the design of the low background neutrino detector and the oscillation analysis performed. From the deficiency between the expected and measured number of electron anti-neutrinos a value of sin²(2{theta-13}) = 0.104 ± 0.03(stat) ± 0.076(syst) was found for rate only analysis and 0.086 ± 0.041(stat) ± 0.030(syst) with the rate and spectral energy shape analysis.