Study and optimization of the IXPE polarization-sensitive detectors

Recently selected by NASA as the next SMall EXplorer (SMEX) mission for a launch in mid 2021, the Imaging X-ray Polarimetry Explorer (IXPE) will be the first mission entirely dedicated to X-ray polarimetry in the 2-10 keV energy band. At the heart of each of its three telescope systems is a Gas Pixel Detector (GPD), a polarization-sensitive imaging detector invented and developed in Italy. Thanks to its capabilities, IXPE will expand the X-ray view of the Universe, simultaneously adding polarization measurements (degree and angle) to the set of source properties currently measured in the X-ray band (spectrum, variability, and morphology). The main theme of this thesis is the study and the optimization of polarization-sensitive detectors that will be on-board IXPE. After a brief review of the X-ray polarimetry and a detailed presentation of the IXPE mission and its scientific goals, I focus on my research activity on the development of the Monte Carlo simulation of the GPD and the realization of a new simulation framework designed to produce fast and realistic IXPE observations.