Calibration of the HEPD detector on board CSES and preliminary analysis on galactic proton flux

This work presents HEPD in the theoretical reference frame of the experiment, as part of the CSES mission. It describes in detail the energy reconstruction of an event, highlighting the importance of MC software and digitization in calibration and data analysis. Finally, some of the first results of proton fluxes in the context of cosmic ray physics are reported. The 1st chapter of this work describes the physics reference frame of the experiment HEPD. It illustrates the main features of cosmic ray physics and GCR (Galactic Cosmic Rays), including origin, propagation and solar modulation; a general description of the main scientific objectives of CSES, such as Van Allen belts and solar physics, is given. In the 2nd and 3rd chapter, general outlines of CSES mission and of the HEPD experiment are exposed respectively. Chapter 2 presents the general features of CSES, together with an overall description of its payloads. Chapter 3 focuses on the HEPD instruments geometry, electronics and general functioning mode. Chapter 4 introduces the Monte Carlo software of the experiment, to which I personally worked, with particular mention to the digitization procedure and its importance in the data analysis; the energy reconstruction follows, explaining in detail beam test data analysis and calorimeter calibration. Chapter 5 presents the event selections for a galactic proton flux, together with the geometrical factor, the selection cut efficiencies, the live time and the galactic selections. Some preliminary results about the data analysis on cosmic ray fluxes are presented, too, in particular on galactic protons in the energy range observed by HEPD. After conclusions, showing a general review of objectives highlighted in this thesis and results reached with this work, a final chapter is dedicated to the HEPD-02 project, a particle detector foreseen in the CSES-02 mission; a description of its geometry and of the construction of the corresponding MC is explained in detail, showing in particular some structural improvements with respect to HEPD-01 for a full achievement of its scientific objectives.