1. What are Cosmic Rays? A short history What do we know now about CRs CR – their energy spectrum Why all these is interesting? How CRs can be accelerated? Ultra High Energy and GZK Cut-Off Various speculations EAS detection from the Space EUSO, OWL, TUS UHECR simulation and reconstruction Expected Performance Conclusions UHECR detection from the Space Munich March 2004 …by Dmitry Naumov(JINR)

2. Courtesy by V.Naumov

3. A gold-leaf Bennet-type electroscope (ca. 1880s) manufactured by Ducretet. Even very well isolated gold-leaf electroscopes are discharged at a slow rate. … observed by scientists before 1900 J.Elster, H. F.Geitel, C.Wilson investigated this phenomenon and concluded that some unknown source of ionizing radiation existed. Wilson even surmised that the ionization might be “…due to radiation from sources outside our atmosphere, possibly radiation like Röntgen rays or like cathode rays, but of enormously greater penetrating power.” 1900-1901 Soon after, two Canadian groups, Ernst Rutherford and H. Lester Cooke (1903) at McGill University, and J. C. McLennan and E. F. Burton (1902) at the University of Toronto showed that 5 cm of lead reduced this mysterious radiation by 30%. An additional 5 t of pig lead failed to reduce the radiation further. Courtesy by V.Naumov

5. Victor Hess won The Nobel Prize in Physics 1936 "for his discovery of cosmic radiation". Classic references: V.F. Hess, Physik. Zeitschr. 12 (1911) 998. V.F. Hess, Physik. Zeitschr. 13 (1912) 1084. V.F. Hess, Physik. Zeitschr. 14 (1913) 610. Background of the slide: H.E.S.S. (High Energy Stereoscopic System) a next-generation system of Imaging Atmospheric Cherenkov Telescopes for the investigation of cosmic gamma rays in the 100 GeV energy range. Courtesy by V.Naumov

7. Up to now EAS are detected on the Earth ground Today the largest ground detector Pierre Auger in Argentina camps will cover ~3000 km 2 surface and detect both:  Charged particles  Fluorescent light

8. Courtesy by V.Naumov 1 st knee Foot (?) Modulated by solar activity 1 particle per m 2 ×second 1 particle per m 2 ×year 2 nd knee Ankle Fingers (?) 1 particle per km 2 ×year A Bird view of the CR spectrum

9. 1 st knee ~ 3×10 6 GeV GZK ~ 5×10 10 GeV ankle ~ 5×10 9 GeV 2 nd knee ~ 4×10 8 GeV Courtesy by V.Naumov

10. A lower energy data suggests a dominance of the protons… The AGASA data seems to conflict to both Hires and GZK prediction. There is also a 2 times difference in the flux measurement between Hires and AGASA at low energies! Hires is a fluorescent detector AGASA is a charge track detector

11. A brief history of AGASA-HIRES conflict NOW One if the HiRes cameras which has an exposure slightly greater then that of AGASA recorded only 2 events above 10 20 eV compared to 20 expected if AGASA is right. PAST Also HiRes reported data from their stereo system (20% of their monocular exposure). They observed only 1 event with 10 20.5 eV Recently AGASA reported 17 events above 10 20 eV consistent with their previous work. HiRes showed 7 events above 10 20 eV in agreement with AGASA Before 2001 event rate at 10 19 eV reported by different experiments was in agreement at 10-15% level.

12. Haverah Park experiment (England) reassessed their energy spectrum 4 events above 10 20 eV shifted by 30% below 10 20 eV. On top of that…

13. The arrival direction of UHECRs There is a systematic enhancement of events with energy until 10 19 eV correlated to the galactic plane There is a deficit of events correlated to the galactic plane above 10 19 eV Haverah Park indicates a correlation with super-galactic plane (plane with Virgo radio galaxies cluster) above 4.10 19 eV However AGASA, SUGAR and Fly’s Eye do not confirm this result

14. Isotropic distribution of CR events with energy > 10 19 eV observed (Takeda et al., 1999). AGASA Super GZK event distribution. Do UHECRs come from the same Source?

15. Probability of clusters at AGASA Impressive chance probability however Significantly depends on the binning. This is NOT a blind analysis AGASA resolution

16. How UHECRs are accerelated? 1.Top down (TD, Big-Bang Remnants, WIMPs etc) 2.Bottom Up (shock waves, RadioGalaxies, etc) 3.Diffusion acceleration at Newtonian Shocks 4.Unipolar induction (rotating magnetic fields  strong electric field) 5.Non-linear particle-wave interaction 6.Active Galactic Nuclei and Dead Quasars 7.Neutron Stars 8.Gamma Ray Bursts 9.etc… A lot of speculation but nobody knows (and if knows does not tell us) the truth…

17. How UHECRs Propagate?

18. 2.73°K cosmic microwave background (CMB) (GZK) Cutoff E th > 5.10 19 eV Proton Propagation

19. 2.73°K cosmic microwave background (CMB) (GZK) Cutoff Greisen-Zatsepin-Kuzmin (GZK) CutOff E th > 5.10 19 eV

20. The main mechanism Heavy Nuclei Propagation 1.Compton interactions 2.Pair production 3.Photodisintegration 4.Hadron photoproduction t[s] 10 14 10 16

21. Photon Propagation Energy loss is well understood as a pair creation Trough collisions with various radiation fields

22. How to avoid GZK?

23. Z 0 burst from the annihilation with CNB relic neutrinos in Virgo Cluster. The decay products of Z 0 are gamma rays, nucleons and neutrinos, as firmly established by the CERN LEP experiments. Strong neutrino flux @ E>10 21 eV can propagate unattenuated and give us photons, nucleons and pions interacting with CNB! Neutrino can propagate trougth CNB = (n  ) -1 ~ 4 x 10 28 cm Above the size of the horizon (H 0 -1 ~10 28 cm)

24. Galactic Halo Extra Galactic

25. SUSY U (uhecron) Good candidate is g ~ -hadron (gluino containing hadron): QCD sum rules suggests gluballino (gg ~ ). There are two narow allowed windows for g ~ -hadron mass: (1.5-3) GeV/c 2 and (25-35) GeV/c 2 1.5 GeV 1GeV 2GeV

26. Lorenz symmetry violation No reason to believe for a universal scale below which the Lorenz symmetry is violated. However Local Lorenz Invariance could be violated With anomalous kinematicsWithout anomalous kinematics

27. Lorenz symmetry violation No reason to believe for a universal scale below which the Lorenz symmetry is violated. However Local Lorenz Invariance could be violated Could exist a maximum attainable velocity for each particle  ik = c i -c k difference in speeds 4w   p E + (m  2 -m p 2 )/E energy conservation If   p >4w 2 / (m  2 -m p 2 ) = 3.5 10 -25 (w/w 0 ) 2 Has no solution no GZK limit

28. Lorenz symmetry violation There are no direct constrains on the parameter   p However we can compare the speed of light to that oh high energy CR which should emit the Cherenkov light if c  < c CR Today constrains:  p  <3.0 10 -23  e  <1.3 10 -13 From CRs of highest energy  e  <1.3 10 -15   <1.0 10 -8 From Multi-TeV  ray observations From SN1987a

29. Spectrum of energy Nature (p, Fe, , … ) Sources unknown! Unknown in addition : Is GZK limit is violated or no ? unknown! What do we know about UHECRs today?

30. Who and How is going to address the problem(s)?

31. Courtesy by C.Lauchaud

32. 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

33. mold production in JINR/Dubna Space qualified carbon-plastic Fresnel mirror to be produced @ “Luch” (Syzran) Mirror mold section Ring number Measured vs theory Measured - theory [mm]

34. Orbiting Wide Angle Light-collector (OWL) Original concept AirWatch (1996) Improved every year Two satellites flying in formation Angular Resolution: 0.2  Energy Resolution: 14% Aperture: 2X10 6 km 2 ster Duty Cycle ~12% Eff. Aperture: 2.3X10 5 km 2 ster http://owl.gsfc.nasa.gov

35. EUSO: ISS stationed optics 2 m diameter Fresnel lenses  30 o FoV 3 years data taking Now end of Phase A

36. UHECR Atmoshpere shower Air fluoresence Cerenkov light Reflection from the Earth Attenuation in air

38. Description of telescope Optique d’EUSO (NASA) : Lentilles de Fresnel Surface focale: Structure porteuse FS (France) électronique ( Italie et France) PM Multi-anodes ( Japon ) Hamamatsu R5900-M-16/64 Interfaces / Lanceur + Module ISS Structure porteuse intermédiaire « Alenia » (Italie)

40. EUSO Frequently Used Software UNISIM PARIS SLAST S.BottaiE.Plagnol D.Naumov S.Bottai HYBRID METHODS : FULL MC SIMULATION FOR E>Eth, PARAMETRIZATION FOR E<Eth. Good reproduction of fluctuations with Eth=10 17 eV. LPM EFFECT INCLUDED NEUTRINO SIMULATION OF EHE NEUTRINO INTERACTIONS CC+NC Single cherenkov scattering Clouds simulation Common features: 3D Geometry and Earth Curvature hadron-air initial interaction Production of fluorescent and cherenkov light Atmosphere response Energy distribution of electrons in shower (impact on both fluorescent and cherenkov light) Easy configurable atmosphere profiles, attenuation, detector parameters Neurino CC +NC interactions ESAF light production engine D.Naumov, EUSO-SDA-015

41. h=0 km h=100 km An example from LOWTRAN7.1: a vertical transmission from h to  Shower development Atmosphere response

42. Fluorescence in air

43. The Background. The night view of the EARTH @moonless night we expect 500 photons m -2 ns -1 sr -1, corresponding to  0.3 p.e./  s

44. Clouds Reflection of the Earth 22 june 2002

45. EUSO Reconstruction. 1. Incoming direction Hired X,Y pixels allows to recover the shower track direction

46. EUSO Reconstruction. 1. Incoming direction Hired X,Y pixels allows to recover the shower track direction P.Colin, D.Naumov, P.Nedelec, EUSO-SDA-REP-016

47. EUSO Reconstruction. 1. Incoming direction Hired X,Y pixels allows to recover the shower track direction P.Colin, D.Naumov, P.Nedelec, EUSO-SDA-REP-016 Assuming infinite pixel resoltion

48. EUSO Reconstruction. 1. Incoming direction Hired X,Y pixels allows to recover the shower track direction

49. EUSO Reconstruction. 2. Altitude of Shower Maximum Use of Cherenkov echo H ma x X ma x P.Colin, D.Naumov, P.Nedelec, EUSO-SDA-REP-016 Need for an extra device (LIDAR) to detect the reflective surface (cloud) while the Earth relief must be recovered by other means Cherenkov light is drastically suppresed at zenith angle > 70 deg. (important for neutrino showers)

50. EUSO Reconstruction. 2. Altitude of Shower Maximum Use only fluorescenceUse of Cherenkov echo H ma x X ma x 5km 20 km Time development of two horizonthal showers. Nmax/Ntot ~  (h)

51. EUSO Reconstruction. 2. Altitude of Shower Maximum P.Colin, D.Naumov, P.Nedelec, EUSO-SDA-REP-016

52. EUSO Reconstruction. 3. Energy Statistical limit

53. EUSO Reconstruction. 3. Energy Events were generated by Eric Plagnol with the Model Clouds. - Cloud distribution, types, and population; Overall EUSO instrument efficiency 0.07056 is used with SLAST. Energy, Height of the shower maximum and/or clouds are blind-fold for EUSO. All of them are autonomously analyzed by the shape methods. Two sets of events are provided without identity: GZK and Super-GZK types. Blind-fold testing to reproduce and identify the energy spectrum of two types. Existence or absence of the cloud, (and the type of cloud or its height), if any, is not given but derived by the self-diagnosis. We got quite promising results...People still are not convinced. Let us play a blind game!

54. Shower fit by two Gaussian - Wide Fluorescence and narrow Cherenkov plus Poissonian background noise Thick-Cloud-hitting high Cherenkov peak and close to N max Ground-hitting or low-altitude, thin-cloud hitting PARIS event (Cloud)  E/E (Shape - Cherenkov) = 1.08 x 10 20 eV - 1.19 x 10 20 eV = 3 - 5% at 7 x 10 20 eV.  H max = [H (Fluorescence 5.83 km) - H (Cherenkov 4.22 km)] = 1.61km gives the altitude of clouds H cloud = 1.6km. SLAST (no clouds)  H max = [H (Fluorescence 5.56 km) - H (Cherenkov 5.23 km)] = 0.3km  E/E = 3 - 5% at 7 x 10 20 eV  X max = 7% (Shape) and 2% (Ch).

55. Recovery of energy spectra

57. Conclusions Whatever the scientific objectives are EUSO is a very interesting and power tool to enter the game! EUSO will collect in 3 years ~few 1000 of events EUSO will be able to separate (to some extent) p, Fe and neutrino 20-30% error for the energy measurement is expected