The new High Energy Particle Detector (HEPD-02) on board the CSES-02 satellite

The China Seismo-Electromagnetic Satellite (CSES) is a multi- payload space observatory aimed at monitoring the near-Earth environment through the observation of the Van Allen Belts dynamics, the study of solar-terrestrial interactions and the extension at low energies of Cosmic Ray measurements. The first satellite (CSES-01) has been in orbit since February 2018, hosting on board the High Energy Particle Detector (HEPD-01) developed by the Italian LIMADOU collaboration. The launch of the second satellite (CSES-02) is expected at the end of 2024. It will carry HEPD-02, a new high-energy particle detector optimized to detect charged particles, mostly electrons in the 3-100 MeV energy range and protons between 30 and 200 MeV, with good capabilities for identifying light nuclei and detecting Gamma Ray Bursts. The instrument is quite compact (40.36 cm × 53.00 cm × 38.15 cm) and presents important upgrades with respect to its predecessor. It will be the first instrument in space carrying a CMOS pixel tracker designed to achieve 5-micron resolution; and the largest LYSO crystals (15.0 cm × 4.9 cm × 2.5 cm) ever used, as part of the electromagnetic calorimeter. This contribution provides a synthetic description of the HEPD-02 detector on board the CSES-02 mission and summarizes its main characteristics and performance.