1. K. Belov INR Moscow April 2005 Yulia Fedorova & Konstantin Belov High Resolution Fly’s Eye (HiRes) Collaboration International Symposium on Ultra High Energy Cosmic Rays, Institute for Nuclear Research, Moscow, April 15, 2005 Molecular atmosphere: radiosonde data and HiRes model Columbia University University of Adelaide University of New Mexico Rutgers University University of Montana Los Alamos National Laboratory University of Tokyo

2. K. Belov INR Moscow April 2005 HiRes Mass Composition and Cross- Section. Both measurements can be affected By atmospheric uncertainty

3. K. Belov INR Moscow April 2005 UHECR detectors and gravity waves Obstructed air motion generates (a) downslope winds (Foehn, El Zonda) and (b) “gravity” waves leeward of the mountain (analogous to deep ocean waves) called “mountain waves” or “lee-waves”. HiRes, AUGER South, TA are all located on high plateaus leeward (down-wind) of a major mountain range. AUGER south is located downwind of the Andes: a high and narrow range exposed to unobstructed ocean winds on its western slopes

4. K. Belov INR Moscow April 2005 Outlines Atmospheric stability Radiosonde data vs HiRes model Atmosphere uncertainty and EAS parameters –Energy –Xmax Conclusions

5. K. Belov INR Moscow April 2005 HiRes Atmospheric model 1976 US Standard Atmosphere 3 seasonal profiles: winter, summer, spring/fall For reconstruction the model is picked according to the season. Dec, Jan, Feb – winter June, July, Aug – summer All other months – spring/fall.

6. K. Belov INR Moscow April 2005 US Standard Atmosphere //------ July 45 degree north --------- 0.0, 1.19E-03, 1013.5, 296.22, 1.0, 1.08E-03, 902.2, 291.14, 2.0, 9.76E-04, 801.5, 286.19, 3.0, 8.85E-04, 710.3, 279.78, 4.0, 8.00E-04, 627.8, 273.55, 5.0, 7.21E-04, 553.3, 267.43, 6.0, 6.48E-04, 486.3, 261.3, 7.0, 5.83E-04, 425.9, 254.75, 8.0, 5.22E-04, 371.8, 248.21, 9.0, 4.66E-04, 323.4, 241.69, 10.0, 4.15E-04, 280.3, 235.17, 11.0, 3.69E-04, 241.9, 228.65, 12.0, 3.26E-04, 207.8, 222.15, 13.0, 2.87E-04, 177.8, 215.65, 14.0, 2.45E-04, 151.8, 215.65, 15.0, 2.09E-04, 129.5, 215.65, 16.0, 1.79E-04, 110.5, 215.65, 17.0, 1.52E-04, 94.35, 215.65, 18.0, 1.29E-04, 80.56, 216.85, 19.0, 1.10E-04, 68.85, 218.05, 20.0, 9.36E-05, 58.89, 219.25, 21.0, 7.97E-05, 50.42, 220.45, 22.0, 6.79E-05, 43.20, 221.65, 23.0, 5.79E-05, 37.04, 222.85, 24.0, 4.94E-05, 31.79, 224.05, 25.0, 4.22E-05, 27.31, 225.25, 26.0, 3.61E-05, 23.47, 226.45, 27.0, 3.09E-05, 20.19, 227.65, 28.0, 2.64E-05, 17.39, 229.75, 29.0, 2.25E-05, 15.00, 231.85, 30.0, 1.93E-05, 12.95, 233.95, //------ January, 45 degree north --------- 0.0, 1.30E-03, 1018.00, 272.59, 1.0, 1.16E-03, 897.30, 269.00, 2.0, 1.04E-03, 789.60, 265.43, 3.0, 9.23E-04, 693.70, 261.85, 4.0, 8.28E-04, 607.90, 255.77, 5.0, 7.41E-04, 531.00, 249.74, 6.0, 6.61E-04, 462.40, 243.7, 7.0, 5.88E-04, 401.20, 237.68, 8.0, 5.22E-04, 346.80, 231.66, 9.0, 4.61E-04, 298.70, 225.66, 10.0, 4.06E-04, 256.20, 219.65, 11.0, 3.49E-04, 219.30, 219.15, 12.0, 2.99E-04, 187.60, 218.65, 13.0, 2.56E-04, 160.40, 218.15, 14.0, 2.20E-04, 137.10, 217.65, 15.0, 1.88E-04, 117.20, 217.15, 16.0, 1.61E-04, 100.10, 216.15, 17.0, 1.38E-04, 85.49, 216.15, 18.0, 1.18E-04, 72.98, 215.65, 19.0, 1.01E-04, 62.28, 215.15, 20.0, 8.60E-05, 53.13, 215.15, 21.0, 7.34E-05, 45.33, 215.15, 22.0, 6.26E-05, 38.68, 215.15, 23.0, 5.34E-05, 33.00, 215.15, 24.0, 4.56E-05, 28.15, 215.15, 25.0, 3.89E-05, 24.02, 215.15, 26.0, 3.32E-05, 20.49, 215.15, 27.0, 2.83E-05, 17.48, 215.15, 28.0, 2.41E-05, 14.92, 215.95, 29.0, 2.05E-05, 12.74, 216.75, 30.0, 1.74E-05, 10.89, 217.55, //------- Mid-latitude, Spring/Fall ------ 0.0, 1.23E-03, 1013.25, 288.15, 1.0, 1.11E-03, 898.7, 281.65, 2.0, 1.01E-03, 795.0, 275.15, 3.0, 9.09E-04, 701.1, 268.65, 4.0, 8.19E-04, 616.4, 262.15, 5.0, 7.36E-04, 540.2, 255.65, 6.0, 6.60E-04, 471.8, 249.15, 7.0, 5.90E-04, 410.6, 242.65, 8.0, 5.25E-04, 356.0, 236.15, 9.0, 4.66E-04, 307.4, 229.65, 10.0, 4.13E-04, 264.4, 223.15, 11.0, 3.64E-04, 226.3, 216.65, 12.0, 3.11E-04, 193.3, 216.65, 13.0, 2.66E-04, 165.1, 216.65, 14.0, 2.27E-04, 141.0, 216.65, 15.0, 1.94E-04, 120.4, 216.65, 16.0, 1.65E-04, 102.9, 216.65, 17.0, 1.41E-04, 87.87, 216.65, 18.0, 1.21E-04, 75.05, 216.65, 19.0, 1.03E-04, 64.10, 216.65, 20.0, 8.80E-05, 54.75, 216.65, 21.0, 7.49E-05, 46.78, 217.65, 22.0, 6.37E-05, 40.00, 218.65, 23.0, 5.43E-05, 34.22, 219.65, 24.0, 4.63E-05, 29.30, 220.65, 25.0, 3.95E-05, 25.11, 221.65, 26.0, 3.37E-05, 21.53, 222.65, 27.0, 2.88E-05, 18.47, 223.65, 28.0, 2.46E-05, 15.86, 224.65, 29.0, 2.10E-05, 13.63, 225.65, 30.0, 1.80E-05, 11.72, 226.65 Height (above MSL), density, pressure, temp.

7. K. Belov INR Moscow April 2005 Ground Temperature and Pressure Variations Radiosonde data

8. K. Belov INR Moscow April 2005 Vapor Pressure and Relative Humidity Variations (ground level) Radiosonde data

9. K. Belov INR Moscow April 2005 Pressure variations Radiosonde data

10. K. Belov INR Moscow April 2005 Normalized Pressure variations Radiosonde data Mean pressure – averaged over the first 5 years. 6 th -year not complete, so was not taken into account.

11. K. Belov INR Moscow April 2005 Pressure variations Radiosonde data

12. K. Belov INR Moscow April 2005 Normalized Pressure variations Radiosonde data Mean pressure – averaged over the first 5 years. 6 th -year not complete, so was not taken into account.

13. K. Belov INR Moscow April 2005 Temperature Profile HiresAuger

14. K. Belov INR Moscow April 2005 Radiosonde Data vs HiRes Model

15. K. Belov INR Moscow April 2005 Transmission Correction

16. K. Belov INR Moscow April 2005 Uncertainty in pressure difference.

17. K. Belov INR Moscow April 2005 Energy correction Eng2 – radiosonde Eng0 – Standard HiRes model Tails cut. Each event reconstructed With radiosonde data and Compared with reconstruction Using HiRes model.

18. K. Belov INR Moscow April 2005 X max correction Xmax2 – radiosonde Xmax0 – HiRes model HiRes underestimates Xmax By 13 g/cm2. Each event reconstructed With radiosonde data and Compared with reconstruction Using HiRes model.

19. K. Belov INR Moscow April 2005 Conclusions Molecular atmosphere profile is very stable. Large-scale seasonal changes prevail over day-today fluctuations. Hires atmospheric model very good describes Utah atmosphere The transmission coefficient correction (and and energy relative uncertainty due to this correction) is about 1-2%. Systematic error in X max is estimated as 13 gm/cm2