Measurement of nuclear fragmentation cross section for a 400 MeV/u 16O beam on a polyethylene target with the FOOT experiment

Hadrontherapy is an external radiation therapy for cancer that uses beams of charged particles, protons or heavier ions, to target the tumor and prevent its proliferation. When entering a medium, due to electromagnetic interactions with electrons, a charged particle releases most of its energy just before stopping in the so-called Bragg peak, whose position depends on the initial energy of the particle. The energy release is thus concentrated in the tumor area, minimizing damage to surrounding healthy tissues. Nuclear interactions can also occur, causing fragmentation of human body nuclei and of the beam, possibly changing the dose release profile. A precise understanding of these interactions is therefore needed. Another field that benefits from nuclear interaction measurements is space radioprotection. The main concern of human missions in deep space is protecting astronauts from the harsh space radiation environment. To provide effective shielding, nuclear interaction data are fundamental to develop accurate models and evaluate health risks. However, nuclear fragmentation cross section data are very limited. The FOOT (FragmentatiOn Of Target) experiment aims to fill this gap by measuring the nuclear fragmentation double differential cross section with respect to the kinetic energy of the fragments and their emission angle, with a precision within 5%. The experiment is composed of two different setups: an emulsion setup, optimized for light fragments, and an electronic setup. In this thesis I analyze a data sample taken at GSI (Darmstadt, Germany) in July 2021, with the electronic setup, with a 400 MeV/u 16O beam on a polyethylene (C2H4) target, obtaining a first evaluation of total and angular differential cross section for different fragment charges. Using a previous result with a graphite (C) target, the cross section for a proton target is also obtained. When a comparison is possible, the results are in agreement with the limited data currently available.