Clusters of galaxies are unique systems in the universe. Being the largest gravitation- ally bound and virialized structures, they are “at the crossroads of astrophysics and cosmology”. They host three main components: galaxies; hot, optically-thin plasma and non-baryonic dark matter. The Sunyaev–Zel’dovich effect, arising from the scattering of the photons of the cosmic microwave background off the free electrons in the ionized intra-cluster plasma, is one of the most valuable probes of cluster properties. Among these, cluster mass is the most important one, since it plays a central role in cluster-based cosmological studies. Direct measurements of the Sunyaev–Zel’dovich signal allow the investigation of the thermal pressure and of the projected velocity of the intra-cluster plasma along the observer’s line of sight. This Thesis is devoted to the study of these quantities, which both play a relevant role in getting accurate estimates of cluster masses. More specifically, we focussed on: (i) the development and validation of an improved imaging algorithm to produce maps of the thermal component of the Sunyaev–Zel’dovich effect; (ii) an application of the kinetic Sunyaev–Zel’dovich effect to investigate cluster rotation. To this end, we used microwave data from real cluster observations with the Planck satellite, and mock data from a set of hydrodynamical simulations of galaxy clusters. Both these studies yielded interesting results, which can shed new light on largely addressed but yet unresolved issues in modern cluster science.
Astrophysics with the Sunyaev-Zel’dovich effect in clusters of galaxies / Baldi, ANNA SILVIA. - (2020 Jan 16).
|Titolo:||Astrophysics with the Sunyaev-Zel’dovich effect in clusters of galaxies|
|Data di discussione:||16-gen-2020|
|Appartiene alla tipologia:||07a Tesi di Dottorato|