Status of the Space Experiment TUS for UHECR Study

The TUS space experiment for studying the energy spectrum, the composition and arrival directions of Ultra High Energy Cosmic Rays (UHECR) is in preparation. R&D stage of the TUS project is close to the end. At present the rst prototypes of the detector are under testing. The PM tube selected for the TUS photodetector and the corresponding electronics are being tested on the Moscow State University satellite iTatianai. The preliminary results of measurements of the UV light from the atmosphere by this detector and the uorescent radiation of shower electrons measured in the MACFLY experiment at CERN are presented. At Mexican mountains the TUS prototype started to measure the temporal proles of UV signals in the atmosphere. Design and development of the space mirror-concentrator was continued: the rst samples of the mirror segments were constructed and tested.