1. D.V.Skobeltsyn INP Moscow State University “Energia” Korolev (Rocket Space Corporation) “Luch” Syzran SCTB, Russia JINR, Dubna, Russia Mexico University, Mexico Ewha Womans University Seoul, South Korea UHECRs measurements from Space via detection of fluorescent and Cherenkov light produced by EAS TUS: Goal: 1.5 m diameter Fresnel Mirror Background measurement dozens events per year with E>10 20 eV TUS2: Double TUS KLYPVE: 3.5 m diameter Fresnel Mirror #10 3 events per year #10 2 events with E>10 20 eV V. Alexandrov, D. Bugrov, G. Garipov, N.Kalmykov,B.Khrenov, M. Panasyuk, S.Sharakin, A. Silaev, I. Yashin V. Grebenyuk,M. Finger, A. Zhuchkova, D. Naumov, Nguen Man Sat, A. Olshevsky, B. Sabirov, L. Tkatchev, N. Zaikin O. Saprykin, V. Syromyatnikov E. Bitkin, S. Eremin, A. Matyushkin, F. Urmantsev A. Cordero, O. Martinez, E. Morena, C. Robledo,H. Salazar, L. Villaseeor, A. Zepeda I. Park NIO KOMPAS, Czech Republic M. Shonsky Technical University, Prague, Czech Republic J. Zicha

2. Ultra High Energy Cosmic Rays (UHECRs) GROUND BASED DETECTOR DATA ON UHECR Energy, eV 1 st knee Modulated by solar activity 1 particle per m 2 ×second 1 particle per m 2 ×year 2 nd knee Ankle 1 particle per km 2 ×year  What is their origin?  Top-down? Bottom-up? Source?  What is the nature of UHECRs?  p,Fe,,   What is their spectrum?  consistent with GZK ( p+  2.7  p +  0 ) ? Energy, eV aqqqq Energy, eV

3. Concept of TUS/TUS2 space free flyer 16x16 PMTs Fresnel mirror 10 rings Focal distance is 1.5 m Field of View is 7.3 o

4. mold production in JINR/Dubna Space qualified carbon-plastic Fresnel mirror to be produced At “Luch” (Syzran) Mirror mold section Ring number The light spread radius on the focal plane: 90% 80% 70% Measured vs theory Measured - theory [mm]

5. SLAST package: 1.3D Geometry 2.Various Atmosphere profiles 3.GIL parameterization of CORSIKA 4.Hillas parameterization for the energy distribution 5.First interaction of nuclei or neutrino from cross-section 6.Fluorescence as a function of altitude in the atmosphere and the shower age 7.Cherenkov light simulation 8.LOWTRAN7.1 atmosphere response Electronics Simulation: 1.Analog & Digital 2.Multi-Level trigger system with two modes: “vertical” & horizontal showers Events per year TUS KLYPVE

6. Reconstruction: (under way) 1.Arrival direction 2.H max and X max for : 1.Golden events 2.Fluorescent events 3.Energy TUS relative resolution of H max as a function of zenith angle for: Golden Events Fluorescent Events Cherenkov echo gives us a reference point to reconstruct H max for golden events. Temporal profile of (quasi) horizontal showers is sensitive to H max. This makes possible to reconstruct H max (and X max ) for events without Cherenkov echo. Both methods are complementary to each other.

7. The real background  need for all space based experiments dozens of events above 10 20 eV  more than the world current statistics (with overall sky coverage) TUS will measure in one year: TUS as a space based experiment will: Test the approach preparing for the next generation of experiments: EUSO, KLYPVE,OWL and OTHERS!