On the CTA capabilities in resolving sources in the galactic plane survey

The CTAO will be the next generation of Imaging Atmospheric Cherenkov Telescopes array, breaching the limits of the current facilities and covering energies from 20 GeV up to 300 TeV. One of the major scientific objectives of CTAO will be the Galactic Plane Survey which will provide the first complete very-high-energy scan of the entire Galactic plane. This complete census of the very-high energy gamma-ray source populations will allow us to identify promising targets for follow-up observations. However, the improved sensitivity of CTAO will lead to a higher probability of source confusion, a problem that concerns multiple overlapping sources and multiple detections related to a single extended source. This thesis project aims at studying the specific problem of the impact of the source confusion in resolving sources in the Galactic Plane Survey. The full work is based on simulations and subsequent analysis in a systematic way of different kind of confused regions, starting with the simplest cases in which two pointlike sources have been simulated with the same spectra, then changing spectral and spatial parameters of these two sources. This will allow us to draw clear conclusions about how source confusion will influence future observations and to fulfil the capabilities of CTAO. Here, through the computation of the two sources detection rate, it was possible to see when two sources become distinguishable from each other for every scientific case considered, changing the spatial and spectral parameters of the sources. Moreover, it was possible to compare the parameter values coming from the fitting process with the simulated ones when the two sources were actually resolved and to see how source confusion affected the sources when a single target has been detected. In particular, the presence of a very extended source with a “smaller" one results to be a good example of how a diffuse emission influences the detection of a source.