1. Presented for Arnulfo Zepeda On behalf of the Mexican Collaboration Sep. 2000 PHYSICS AND ASTROPHYSICS OF ULTRA HIGH ENERGY COSMIC RAYS BUAP CINVESTAV UMSNH UNAM Material selected and prepared for Rebeca López

2. GOAL To develop physics and astrophysics of ultra high energy cosmic rays through the participation of Mexican scientists in the construction of the Pierre Auger Observatory. R. López

3. CONTENTS Antecedents on cosmic rays. The Pierre Auger Observatory. The Mexican Participation (this proposal). R. López

4. ANTECEDENTS Some major discoveries made with cosmic rays The positron (the first antimatter sample), 1933. Extended air showers, 1938. The muon (first relative of the electron), 1943. The pion (the carrier of nuclear interactions, postulated by Yukawa), 1947. Particles with strangeness, 1947. R. López

5. Technics for detection of cosmic rays

6. COSMIC RAY FLUX Cosmic rays are produced in explosive astrophysical events. The low and medium energy spectrum is reasonable weel understood. R. López

8. The complete diffuse background radiation over the spectral region 10 -9 -10 20 eV.

10. ULTRA HIGH ENERGY COSMIC RAYS Cosmic rays may be produced with ultra high energy in exotic sources. They may be further accelerated in strong magnetic fields and plasma shock waves. Then they travel in the interstellar medium, which is never empty. R. López

12. Possible sources of high energy cosmic rays

14. XZ Tauri

15. HH 30

16. ULTRA HIGH ENERGY COSMIC RAYS The interstellar medium is filled with low density radiation, the cosmic microwave background radiation, which originated during the early live of the Universe, at the time of the formation of atoms, at about 400,000 years after its birth. Cosmic rays interact with the CMBR and if their energy is high enough, then their energy materializes into matter, pions are produced with high probability. Thus high energy cosmic rays loose soon their energy. R. López

19. PROCESSES ON THE CMBR

21. THE GZK CUTOFF There is a limit, at around 5 X 10 19 eV to the energy with which cosmic rays may arrive to the Earth from far away (50 Megaparsecs) This is the GZK cutoff. R. López

23. AGASA Energy Spectrum

24. Implications of events beyond the GZK cutoff Suggest the existence of exotic sources? - Quasi-stable massive particles. - Supersymmetric matter. - Topological defects. Violation of Lorentz invariance? R. López

25. EXPOSURES OF UHECR DETECTORS. R. López

26. EXPOSURES OF UHECR DETECTORS. R. López

27. PIERRE AUGER OBSERVATORY R. López

28. The shower

29. MAIN OBJECTIVE OF THE PIERRE AUGER OBSERVATORY To understand the origin and nature of the ultra high energy cosmic rays, one of the major mysteries of modern physics. R. López

30. GOALS OF THE PIERRE AUGER OBSERVATORY Detect a good number of ultra high energy events. Measure with precision the energy of the primary cosmic particle. Determine the incoming direction. Identify the nature, type of particle. R. López

31. Consequences of the Pierre Auger Observatory data In astrophysics. In the theory of elementary particles. R. López

32. Hybrid Detector

35. How water Cherenkov detectors work

37. SCHEME OF THE FLUORESCENCE DETECTOR R. López

41. SIMULATION The computer simulation of - The shower - The detectors - The electronics Shows that the designed observatory will fulfill its objectives. R. López

42. Sites of the Pierre Auger Observatory  

43. Auger Observatory Exposure Sky as seen by observatories, 60° max shower zenith angle. North --> red, South --> green.

45. Pampa Amarilla Site

46. On March 17th 1999 work at the site in Mendoza began. Construction will continue till 2003 although observations will begin by 2001 R. López

47. The first water Cherenkov detector in Malargue

48. Plan of a Fluorescence Detector Building.

49. Los Leones R. López

50. Construction of the Central Station Building.

52. International Collaboration Metting

53. Cost and contributions The total cost of both observatories is 100 million dollars. Approved: Argentina CNEA 10,000 Mendoza 5,000 Brazil 2,000 France 2,300 Germany 5,500 Mexico 300 Slovenia 500 UK 1,000 US 9,000 35,600 R. López

54. Cost and contributions Pending approval: Australia 600 Bolivia 30 China 1,000 Greece 200 Italy 3,200 Mexico 2,650 Poland 50 ------ 7,730 TOTAL 43.300 The rest of the countries in the collaboration are about to submit their applications. R. López

55. Schedule Construction of Southern Observatory Start: March 1999 End: end of 2003 First face: Engineering Array: 40 WCDs and 2 FDs Communication network Data collection system R. López

56. Schedule End construction: end of 2001 Start taking data: January 2002 Construction of Northern Observatory Start: 2003 End: 2005 R. López

57. Finance Board Agreement for the Organization, Management and Funding of the Pierre Auger Observatory Among Science Founding Agencies of Countries in the Pierre Auger Collaboration Signed at Mendoza, Argentina, March 16, 1999. R. López

58. THE MEXICAN GROUP R. López

59. Participants R. López

60. Specific goals of the Mexican grup Tecnological Development. Research activities. Involve the national industry. R. López

61. Fuorescence Detector Design of optical system (special recognition by the project management). Electronics. Development of a tester for mirror quality. R. López

62. Surface Detector Water Purity. Reflective properties. Methods of calibration and monitoring. Requirements for local trigger. R. López

63. Surface Detector Design and construction of the container and of the liner: local development and international coordination (by the task leader). R. López

64. Surface Detector Design and development of the central triggering system and of the data acquisition system. Installation of first tanks. Installation and operation of the array of surface detectors. R. López

65. Rotoplas R. López

66. Computer simulation - Atmospheric shower. - Response of the detectors. - Reconstruction of data. - Test of high energy hadronic interaction models. R. López

67. Students who have finished their thesis R. López

68. Students working on their thesis R. López

69. Students to graduate between 2001 and 2004 R. López

70. BUDGET FOR THE MEXICAN PROGRAM in thousands of US dollars. R and D (travel, computers, prototype components) 1996.... 35 1999.... 60 2000.... 42 (Cinvestav) 2000....130 (BUAP) 2001-4...328 THIS PROPOSAL Observatory components 2000.... 300 (BUAP) 2001-4..2650 THIS PROPOSAL R. López