The High Energy Cosmic Radiation Facility onboard China's Space Station

The High Energy cosmic-Radiation Detection (HERD) facility is one of several space astronomy payloads onboard China's Space Station, which is planned for operation starting around 2020. It is designed as a next generation space facility focused on indirect dark matter search, precise cosmic ray spectrum and composition measurements up to the knee energy, and high energy gamma-ray monitoring and survey. HERD is mainly composed of a high granularity cubic calorimeter (CALO) with deep absorption length surrounded by micro-strip silicon trackers (STKs) from five sides, thus maximizing the geometrical acceptance. An overall description of the design will be described. Moreover, R&D is under way for reading out the LYSO signals with optical fiber coupled to image intensified CCD (ICCD) and the prototype of 1/40 CALO for beam test at CERN.