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Earth's atmosphere and cosmic rays (the point of view of an atmospheric physicist).

Earth's atmosphere and cosmic rays (the point of view of an atmospheric physicist). Vincenzo Rizi (vincenzo.rizi@aquila.infn.it) Dipartimento di Fisica Università Degli Studi - L’Aquila -Italy. Rossella Caruso, Aurelio Grillo, Marco Iarlori, Sergio Petrera,

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Earth's atmosphere and cosmic rays (the point of view of an atmospheric physicist).

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  1. Earth's atmosphere and cosmic rays (the point of view of an atmospheric physicist). Vincenzo Rizi (vincenzo.rizi@aquila.infn.it) Dipartimento di Fisica Università Degli Studi - L’Aquila -Italy Rossella Caruso, Aurelio Grillo, Marco Iarlori, Sergio Petrera, Dipartimento di Fisica Università Degli Studi - L’Aquila Italy, Laboratori Nazionali del Gran Sasso, Istituto Nazionale di Fisica Nucleare First International Workshop on Air Fluorescence Salt Lake City Utah October 5-8, 2002

  2. Summary • Planetary atmosphere as a calorimeter: atmospheric parameters and nitrogen fluorescence yield. • In particular, the effect of atmosphere parameterization and/or local meteorological measurable parameters. • Atmospheric transmission of fluorescence light and determination of energy release by UHECR. • Role of the aerosol transmission • Estimation of aerosol transmission (with real data). • Advantages of Raman lidar in measuring the aerosol transmission.

  3. Residence times Individual species Turbulent mixing dominant at low altitudes (<120km) i.e., mixing ratios ~ constant with altitude ~2x107 years ~3x103 years 78.084% Relevant for inversion of Lidar Raman data, see later! accumulative 20.946% Trace gases 0.036% ~6 years 0.934%

  4. National Space Science Data Center NASA Goddard Space Flight Center Greenbelt, MD 20771, USA Atmospheric models and their use in the estimation of air fluorescence yield and light transmission. Models of preference for specialized tropospheric/lower stratosphere work. Homogeneous mixing Perfect gas Hydrostatic equilibrium Partial list of available models ...

  5. U.S. Standard Atmosphere 1976 NOAA/NASA/U.S.Air Force (<32km)  ICAO standard atmosphere steady state atmosphere for moderate solar activity based on rocket and satellite data + perfect gas theory parameters listed: atmospheric temperature, pressure, density, … in 1966 supplement 5 northern latitudes for summer and winter. Availability: the Fortran code can be obtained from Public Domain Aeronautical software. References: U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, Washington, D.C., 1976.

  6. Atmospheric Handbook 1984 NOAA/National Geophysical Data Center (NGDC) compilation by V.E. Derr parameters listed: atmospheric parameters for scattering … calculations Availability: from NGDC via anonymous ftp. References: V. E. Derr, Atmospheric Handbook: Atmospheric Data Tables Available on Computer Tape, World Data Center A for Solar-Terrestrial Physics, Report UAG-89, Boulder, Colorado, 1984.

  7. COSPAR (Committee on Space Research) International Reference Atmosphere: CIRA 1986 compilations (Fleming et al., 1988) of ground-based and satellite measurements (Oort, 1983, Labitzke et al., 1985) parameters listed: temperature, pressure, densities ... monthly mean values … for the latitude range 80N to 80S Availability: from NSSDC's anonymous FTP site References: E. L. Fleming, et al., Monthly Mean Global Climatology of Temperature, Wind, Geopotential Height and Pressure for 0-120 km, NASA, Technical Memorandum 100697, Washington, D.C., 1988. A. H. Oort, Global Atmospheric Circulation Statistics 1958-1983, NASA, Professional Paper 14, 180 pp., Washington, D.C., 1983. K. Labitzke, J. J. Barnett, and B. Edwards (eds.), Middle Atmosphere Program, MAP Handbook, Volume 16, University of Illinois, Urbana, 1985.

  8. How these “atmospheres” compare … parameters relevant for air fluorescence yield and light transmission? Seasonal variability For a typical GAP site

  9. Seasonal variability

  10. Seasonal variability

  11. Dipartimento di Fisica Università Degli Studi - L’Aquila Italy REAL DATA: Local atmospheric parameters recorded by means of balloon borne meteorological radiosoundings. Vaisala radiosondes measure upper air temperature, humidity and pressure, and upper air windspeed and direction, as they rise to their maximum altitude of ~30 km.

  12. L’Aquila, Italy 42.35N, 13.22E, 683m a.s.l. Seasonal variability  sensors systematics Same atmosphere of a typical GAP site?!

  13. L’Aquila, Italy 42.35N, 13.22E, 683m a.s.l. Seasonal variability  sensors systematics

  14. Outlines - atmospheric models below 20kmmid-latitude seasonal variability pressure up to 20% temperature 28% density 48% Outlines - meteorological observations below 20km42N (L’Aquila - Italy) seasonal variability+sensors systematics pressure 2  10% temperature 4  8%

  15. Atmospheric local parameters variability and air fluorescence yield

  16. Nitrogen fluorescence A.N. Bunner, 1964. Keilhauer, B. et al., Auger technical note GAP-20012-022

  17. , Fluorescence Yield (photons per meter per electron) Kakimoto et al., A measurement of the air fluorescence yield, Nucl. Instr. And Meth. A, 372, 527-533, 1996. Nagano, M. and A.A. Watson, Observations and implications of the UHECR, Rev. Of Modern Phys. 72, 2000 AIR FL(uorescence) Y(ield)approach Paolo Privitera N, Atmospheric number density T, Atmospheric temperature ’s, ’s, constants O-th approx.!

  18. Approaches …to minimize the errors from atmospheric parameters variability Adiabatic model, combined with local ground temperature and pressure measurements. Martin, G., and J.A.J. Matthews,GAP 1999-037, 1999 and/or Local balloon borne meteorological radiosoundings. Forschungszentrum Karlsruhe - Institut für Kernphysik Keilhauer, B., et al., GAP 2002-022, 2002

  19. Atmospheric transmission of fluorescence light.

  20. AFD light measurements CR Io(s) z T’s s AFD IAFD(s) CR cosmic ray AFD Auger Fluorescence Detector T’s transmission functions s range; z altitude

  21. AFD light measurements In a single pixel:

  22. +air fluorescence yield Energy of CR

  23. E: shower energy T: atmospheric transmission It can be easily estimated with sufficient precision …!? High variability … direct measurements with Raman lidar OR strong assumption ... Total atmospheric transmission s range along the line of sight The absorption can be neglected because of the FD optical transmission …!?

  24. Single scattering approx.!

  25. The lidar should/could measure the needed quantities. LIDAR backscattering (bcks.) Laser wavelength Elastic bcks. molecular/Rayleigh & aerosol/Mie Anelastic bcks. Raman (N2, O2 ...) Laser Telescope DAQ

  26. Laser photons Back-scattered photons Atmosphere Atmospheric attenuation: scattering and absorption laser photons collected photons Scattering processes: Rayleigh-Mie scattering Raman scattering Resonant scattering solid angle subtended by the receiver 1/z2 z is the altitude/range

  27. Advantages of Raman lidar vs. Elastic lidar.

  28. Elastic/Rayleigh Lidar signal upward travel downward travel backscattering

  29. Key features of Klett method. Recasting the lidar equation Mandatory assumption! Unknown! Solving for

  30. Key features of Fernald method. Mandatory assumption! Unknown! The Lidar Ratio (LR) is the inverse of the back scattering phase function.

  31. Solving for See …: Scannin lidar based atmospheric monitoring for fluorescent detectors of cosmic showers, D. Veberič, A. Filipčič, M. Horvat, D. Zavrtanik, M. Zavrtanik, submitted, 2002.

  32. Anelastic/Raman Lidar signal upward travel backscattering downward travel

  33. Key features of Raman method. Unknown! Assumption! Unnecessary if Raman signals from O2 and N2 are measured!

  34. Estimation of aerosol transmission with real data.

  35. UV Raman Vertical lidar - Dipartimento di Fisica - Università Degli Studi - L’Aquila o=351nm; Raman=382nm (N2); September 2001 L’Aquila 42oN (rural site) 1/2 hour measurements

  36. 1st step from Raman N2; k=-1 2nd step from Elastic (ext. Coeff.) (bcks coeff.) Taer(z)

  37. Elastic The aerosol transmission function retrieved from real lidar signals (at Univ. AQ) The continuous lines refer to the case in which only the elastic signal is used (the lidar ratio is assumed), the dashed lines with symbols show the transmission calculated using the Raman signal. Raman

  38. Outlines • elastic lidar • More infos on backscattering than extinction. • For simple non-scanning lidar system • the aerosol extinction profiles (i.e., transmission function) • derived by inverting the elastic signal, and assuming • the lidar ratio, might have large systematic errors. • anelastic lidar • reliable aerosol transmission with no assumptions. • A combined Raman/Rayleigh-Mie lidar • measures aerosol extinction and backscattering independently. • best configuration • Scanning Raman/Rayleigh-Mie lidar

  39. Aerosol variability data from RAMAN LIDAR L’Aquila - Italy (~42oN) clear sky above 1500m (virtual Auger FD site)

  40. Lidar ratio (LR) seasonal & altitude variation.

  41. Aerosol extinction seasonal variation.

  42. Aerosol attenuation length seasonal variation.

  43. Aerosol transmission seasonal variation.

  44. Aerosol transmission seasonal variation.

  45. Aerosol extinction and transmission “day” variation.

  46. Outlines - aerosol contribution to light transmission Most of the aerosol in the planetary boundary layer (<3km a.s.l.) clear sky from ~ 1500m a.s.l. relative transmission mean value ~0.85 seasonal variability up to 15% (3) “day” variability (over 3hours - night) ~6%

  47. Status of Raman channel integration in Auger lidar.

  48. Technical details of Raman lidar INFN Torino/Nova Gorica Polytechnic LIDAR Pino TO Elastic Raman O2 Raman N2 laser L: field lens BS: beam splitter NO: notch filter ND: neutral density filter IF: interference filter PMT: photomultiplier telescope

  49. Lidar Auger Malargue - Argentina VERY PRELIMINARY! Malargue Lidar - zenit angle= 90° March 7, 2002 - LR=50, raw resolution 30m Lower limit estimation!. MALARGUE height a.s.l.

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