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The CSES-02 satellite mission seeks to expand our knowledge of the interconnection between the Earth's lithosphere, atmosphere, ionosphere, and magnetosphere. Various instruments will measure the electromagnetic environment around the satellite, which will fly in a Sun-synchronous orbit at approximately 500 km from the ground. The HEPD-02 payload, developed by the Italian Limadou collaboration, is a fundamental component of the mission. It measures the flux of protons (30 to 200 MeV) and electrons (3 to 100 MeV) trapped in the Van Allen Belts, representing an indispensable instrument for studying the ionosphere and the magnetosphere. The HEPD-02 payload mounts LYSO:Ce scintillating crystals to measure the energy of impinging particles. Limadou chose LYSO:Ce due to its fast decay time (40ns), high density (7.1 g/cm3) and high light yield (about 30000 ph/MeV). The module made of LYSO crystals and its relative acquisition system will be sensitive to Gamma-Ray Bursts of energy larger than 2 MeV, a range currently covered by experiments like HXMT, Fermi, and INTEGRAL. With an optimal energy resolution, HEPD-02 will contribute to expanding the coverage of the sky for the detection and study of GRBs. We will report on the sensitivity of HEPD-02 to short and long GRBs, obtained with an Elekta medical LINAC model SL15.

Time-resolved measurements of dierential uxes of low energy charged particles, trapped in the magnetosphere, are interesting for Space Weather characterization and to study the coupling between the lithosphere and magnetosphere, allowing the investigation of the possible correlations between seismic events and particle precipitations from Van Allen Belts. The project of a compact ( 10x10x10cm3 ) particle spectrometer, the Low Energy Module (LEM) as part of the Zirè instrument on board the NUSES space mission is shown.The LEM will be able to perform measurements of energy, direction, and composition of low energy charged particles down to 0.1 MeV kinetic energy. The particle identication capability of the LEM relies on the ∆E-E technique performed by thin silicon detectors.To fulll the size and mass requirements of the whole mission, the particle direction measurement is based on the active collimation technique. The detection concept and the expected LEM performances will be summarized.

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The High-Energy Particle Detector (HEPD-02) is a particle spectrometer developed by the Italian collaboration Limadou within the CSES-02 mission. It has been designed for the detection of electrons (3-100 MeV), protons , and light nuclei, in the near Earth orbit. HEPD-02 is the first detector to use a pixel silicon tracker in space. The Monolithic Active Pixel Sensors (MAPSs) constituting the HEPD-02 silicon tracker are characterized by excellent spatial resolution, lower production costs, higher robustness, and lower noise when compared to traditional microstrip sensors. Nevertheless, stringent requirements on power consumption for space applications lead to a challenging optimization of power demanding processes. Within this paradigm, a tailored Tracker Data AcQuisition (TDAQ) system has been designed. The TDAQ firmware was developed on a Field Programmable Gate Array (FPGA) manufactured by Xilinx: a low-power version of the Artix family with a suitable amount of resources. The parallelization implemented within the TDAQ algorithm was a crucial point in optimizing the limited read-out speed, imposed by power constraints. Nonetheless, the strengths of the TDAQ firmware consists in its modularity and redundancy. In this work, we will present the characterization and the performance of the HEPD-02 TDAQ system.