Performance improvement of an agata segmented germanium detector

This thesis is related to the development of AGATA, which is a new detection systemfor gamma-ray spectroscopy based on the innovative concept of gamma-ray tracking. AGATA is madeup of a large number of high-purity Germanium detectors with the cathode segmentedinto 36 parts, providing the new capability of determining the position of the interactionpoints inside the bulk crystal with a precision of a few mm. Besides the problem of managinga much larger number of channels, the segmentation causes some new problems.One such problem is the electrical coupling between the various channels which causes afold-dependent energy gain that must be corrected away to obtain the best energy resolution.Another problem is the incomplete charge collection affecting interaction events thattake place very close to the segmentation lines, which degrades significantly the shape ofthe sum-energy peaks. This last effect was studied in detail in this thesis resulting in apractical event-by-event correction procedure which improves the energy resolution byup to 20% and increases by up to 50% the useful area of the low energy peaks.