%0 Generic
%A Pürckhauer, Stephanie Sabina
%D 2018
%F heidok:25558
%K Cherenkov Telescope Array  Light concentrators  Event reconstruction  Centaurus A
%R 10.11588/heidok.00025558
%T Characterising light concentrators for CTA  and optimising the data selection to  improve angular resolution and sensitivity
%U https://archiv.ub.uni-heidelberg.de/volltextserver/25558/
%X The Cherenkov Telescope Array (CTA) is the next generation ground-based observatory for gamma-ray astronomy that will reach a performance unprecedented in the field. This thesis focuses on optimising this performance in the core energy range of CTA around 1 TeV. In a first part, the wavelength-dependent angular efficiency of light concentrators for the camera system FlashCam, proposed for the medium size telescopes of CTA, is determined with a dedicated test system. For hexagonal concentrators with three reflective coatings a signal-to-noise ratio enhancement of 2.2 compared to a camera without concentrators is observed. By varying the distance between concentrators and photo-sensors, a fine-adjustment of the angular efficiency increases this ratio by another 3%-5%.  In a second part, the angular resolution and the sensitivity of CTA are studied by means of simulations. By optimising different quality selection cuts on telescope data, sensitivity enhancements of 20%-40% compared to the CTA requirements are reached and 30%-40% for the angular resolution. With the optimised cuts, spatially extended emission models of the radio galaxy Centaurus A are investigated and it is found that the optimised angular  resolution of CTA allows for different theoretical emission models to be discriminated based on the predicted emission regions.