Galaxies like the Milky Way do not exist isolated in space, but occupy a Large Scale Structure (LSS) in the Universe. The LSS is organized in a network of structures (called the Cosmic Web, CW) whose main components are galaxy clusters (at the nodes), connected by filaments, which frame walls. Walls surround vast empty regions called voids. The structures of the CW are made of dark matter, galaxies, and gas. In galaxy clusters in particular, gas is hot and emits in the X-rays, which makes them relatively easy to detect as bright, diffuse X-ray sources. Matter (including gas and galaxies) is accreted by galaxy clusters through the filaments connected to them, which act as highways for matter flow onto structures. As such, studying galaxy clusters connections to the filaments is a very important topic to understand their properties and evolution.
In recent years, a few works have focused on the study of the so-called connectivity-mass relation, i.e. the study of the number of filaments connected to clusters as a function of their mass. However, these studies could only rely on limited samples of clusters within restricted redshift and mass ranges.
The objectives of my work were two: 1) to measure the connectivity-mass relation for an extensive sample of X-ray detected clusters, increasing the mass and redshift range where this relation is analyzed and 2) to study the very low mass regime of groups and the high-mass regime of super-clusters, placing these structures in the context of the CW.