Modélisation, développement et test d'une caméra plasma imprimée en 3D pour les mesures spatiales in-situ

Key phenomena governing the dynamics of space plasmas - including charged particle acceleration, magnetic reconnection and the turbulent dissipation of electromagnetic energy - are multi-scale in nature. In order to understand their role in the Sun-Earth relationship, whether in the solar wind, at the magnetopause or in the Earth's magnetosphere, it is essential to develop instrumentation that is both compact and high-performance, enabling the deployment of satellite constellations. However, the reference instruments used to measure the energy distribution of charged particles have a limited field of view. Adding electrostatic deflection systems circumvents this limitation, with the disadvantage of making these instruments heavier, slowing down their measurement rate, and therefore reducing their performance. In this case, more sensors are needed to achieve the desired performance, impacting satellite size and, ultimately, the number of satellites that can be deployed. The characterization of charged particle fluxes for studying space weather, conducted using compact instruments with a limited field of view, faces the same limitations.The first step in this research project was to develop a method for designing a new range of plasma spectrometers that overcome these limitations. These spectrometers are based on an innovative toroidal topology, offering an instantaneous hemispherical field of view that eliminates the need for electrostatic deflectors. Their planar detection system makes them true plasma cameras. The methods developed have enabled the numerical generation and characterization by simulating a wide range of plasma cameras with different angular resolutions that could meet these various scientific needs.A model instrument was then designed to meet the challenges of space weather applications, with an energy range of up to 22 keV. It features dual ion/electron detection capability, avoiding the need for separate sensors for electron and ion measurements. Intended for nanosatellites, it has a mass of 1.8 kg and a diameter of 19 cm. A 3D-printing manufacturing process and functionalization of the material have been defined and implemented. An ion/electron conversion system using carbon foils, enabling dual use of this plasma camera, has also been developed. An instrument integrating the electrostatic optics and a simplified dual detection system has been tested under an electron beam to obtain precise experimental responses in terms of energy and angle. The beam tests showed behavior very close to the simulation, reinforcing confidence in the numerical modeling. The principle of the conversion system was tested under electron and ion beams. One of the short-term prospects of this thesis is the development, with the support of CNES, of a complete model of this plasma camera, with the aim to demonstrate in orbit the performances of this instrument dedicated to space weather applications.