A MULTI-PROBE APPROACH TO INVESTIGATE OPEN ISSUES IN COSMOLOGY

Abstract

It is a well known fact that the current ”standard” ΛCDM cosmological model provides an excellent fit to many different observations at the price of introducing two exotic, dark components that dominate the mass-energy budget in the Universe today: the Dark matter and the Dark Energy. The study of the large scale structure (LSS) of the Universe provides an effective way to probe the nature of these components, especially the latter. Hence the widespread interest in carrying out large observational programs aimed at probing the LSS over increasingly large fraction of the observable Universe. The thesis is aimed to study efficient methods to analyse the distribution of different mass density tracers that are part of different types of datasets. In the first two methods, I have performed two-point statistical analysis on eROSITA-like galaxy clusters from simulated dataset and Radio sources from TGSS observational datasets, which consisted of 3D and 2D distribution of objects. For the third method I used Euclid survey as a case study, in which, as a part of collaborative work, I developed a fully optimised pipeline to produce photometric redshift galaxy catalogues for tomographic clustering analysis.