Double Chooz is a short-baseline experiment, located at the Chooz power plant, designed to observe the neutrino oscillation signal controlled by the θ13 mixing angle. Part of my scientific research, as a graduate student, was directed towards the development of the software needed for the calibration of the Double Chooz Inner Veto and the analysis of the data associated with this task. I was responsible for the quality tests performed in every photomultiplier prior to its installation. I completed all the necessary measurements and analysed the data, extracting the first set of gains and determining the nominal high voltage values needed to be applied in all photomultipliers. All this information served as valuable input to the detector configuration. I was also responsible for the Inner Veto photomultiplier gain analysis during the first months of data taking. I was also very actively involved in data analysis and the estimations of the various sources of background. I initiated a number of methods to isolate and study the cosmic muon events that activate the detector. Additionally I worked on the estimation of the fast neutron rate registered in the detector. The techniques I put forward played a key role and were used in the first Double Chooz publication. Finally, I developed a set of algorithms to identify and reject an instrumental background, relevant for the Double Chooz detector using topological information of the deposited charge.
