Speaker
Description
The JUpiter ICy moons Explorer (JUICE) is the European Space Agency (ESA) next large class mission to the Jovian system. The mission, planned for a launch in 2022 and a 7.5-year long cruise to the planet, will investigate Jupiter and characterize its icy moons, Callisto, Europa and Ganymede for a period of 3.5 years.
The Jovian system is known to have a harsh and energetic radiation environment with a large population of electrons reaching energies well above 10 MeV. For this reason, the JUICE mission will include the RADiation hard Electron Monitor (RADEM), a low power, low mass radiation monitor, currently under development by LIP, PSI, EFACEC and IDEAS.
RADEM will the first dedicated mission to expand energy measurements of the particle population done by the Galileo Energetic Particle Detector (the JUNO mission does not carry a radiation monitor), while providing housekeeping support to the spacecraft. The instrument consists of three detector heads based on standard silicon stack detector technologies: the Electron Detector Head (EDH), the Proton Detector Head (PDH), and the Heavy Ion Detector Head (HIDH). Because the detectors have limited Field-Of-View, a fourth detector, the Directionality Detector Head (DDH) will measure electron angular distributions. Stacked detectors will cover the following energy range: from 0.3 MeV to 40 MeV for electrons, from 5 MeV to 250 MeV for protons and from 8 to 670 MeV for Heavy Ions from Helium to Oxygen. The role of the DDH is of utmost importance since it has been shown by the Galileo mission that electron fluxes vary spatially e.g. as results of interaction with the Ganymede magnetosphere. Taking it into account will prevent to under or overestimate the spatially integrated particle flux and in consequence the Total Ionizing Dose.
In this work we will present the status of the instrument with a large emphasis on the latest results from proton and low energy electron testing done with the RADEM Engineering Model. The high energy electron testing (up to 40 MeV) done to the detector’s breadboard model will also be presented. The current results show full compliance with the technical requirements. Further calibrations and tests of the Proto-Flight Model are scheduled for the beginning of 2021. The scientific opportunities of the RADEM for the whole JUICE mission will also be discussed.
