Yulia Fedorova

1
Molecular atmosphere radiosonde data and HiRes
model

• Yulia Fedorova Konstantin Belov
• High Resolution Flys Eye (HiRes) Collaboration

International Symposium on Ultra High Energy
Cosmic Rays, Institute for Nuclear Research,
Moscow, April 15, 2005

• Columbia University
• University of Adelaide
• University of New Mexico
• Rutgers University
• University of Montana
• Los Alamos National Laboratory
• University of Tokyo

2
HiRes Mass Composition and Cross-Section.
Both measurements can be affected By atmospheric
uncertainty
3
UHECR detectors and gravity 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

• 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.

4
Outlines

• Atmospheric stability
• Radiosonde data vs HiRes model
• Atmosphere uncertainty and EAS parameters
• Energy
• Xmax
• Conclusions

5
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
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,
//------- 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
//------ 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,
Height (above MSL), density, pressure, temp.
7
Ground Temperature and Pressure Variations
Radiosonde data
8
Vapor Pressure and Relative HumidityVariations
(ground level)
Radiosonde data
9
Pressure variations
Radiosonde data
10
Normalized Pressure variations
Mean pressure averaged over the first 5
years. 6th-year not complete, so was not taken
into account.
Radiosonde data
11
Pressure variations
Radiosonde data
12
Normalized Pressure variations
Mean pressure averaged over the first 5
years. 6th-year not complete, so was not taken
into account.
Radiosonde data
13
Temperature Profile
Hires
Auger
14
Radiosonde Data vs HiRes Model
15
Transmission Correction
16
Uncertainty in pressure difference.
17
Energy correction
Each event reconstructed With radiosonde data
and Compared with reconstruction Using HiRes
model.
Eng2 radiosonde Eng0 Standard HiRes model
Tails cut.
18
Xmax correction
Each event reconstructed With radiosonde data
and Compared with reconstruction Using HiRes
model.
Xmax2 radiosonde Xmax0 HiRes model
HiRes underestimates Xmax By 13 g/cm2.
19
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 Xmax is estimated as 13 gm/cm2