pierre auger observatory jan ridky institute of physics as cr [email protected] for pierre auger...
TRANSCRIPT
![Page 1: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/1.jpg)
Pierre AUGER Observatory
Jan RidkyInstitute of Physics AS CR
For Pierre Auger collaboration
![Page 2: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/2.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 2
astro-particle physics
• spectrum• sources• anisotropy• acceleration• composition• ……
Mission of Pierre Auger Observatory:
• spectrum• interactions• X-sections (p-Air )• acceleration• neutrinos• ….
• spectrum & MC
![Page 3: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/3.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 3
Energy spectrum (a one-century quest!)
1 part/m2/s
Limit forsatellites
knee:1 part/m2/year
32 o
rders
of
magnit
ude!
12 orders of magnitude!
ankle : 1 part/km2/century!
Is there any end?
What kind of end if any?
![Page 4: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/4.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 4
![Page 5: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/5.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 5
The Auger Collaboration
15+2 Countries 60+ Institutions 350+ Scientists
Argentina Netherlands
Australia Poland
Bolivia(*) Portugal
Brazil Slovenia
Czech Republic Spain
France United Kingdom
Germany USA
Italy Vietnam(*)
Mexico (*) Associate countries
![Page 6: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/6.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 6
Pierre Auger Observatory
1 600 detectors 3 000 km2 area1.5 km spacing
![Page 7: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/7.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 7
Pierre Auger Observatory
Hybrid detector
combined virtues ofsurface detector andfluorescence detector
2 independent measurements • cross-calibration• energy and directions• composition
![Page 8: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/8.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 8
4 stations with 24 fluorescence telescopes- each station 180° field of view
CLF
LOMA AMARILLA
![Page 9: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/9.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 9
Pierre Auger observatory - FD
![Page 10: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/10.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 10
Pierre Auger observatory - FDFD = fluorescence detector
mirror: R = 3440 mmarea: 3,6 x 3,6 m2
![Page 11: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/11.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 11
Observatoř Pierra Augera - SDPierre Auger observatory - SD
![Page 12: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/12.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 12
communication antenna
electronics enclosure solar panels
battery box
3 – nine inchphotomultipliertubes
plastic tank with 12 tons of water … 12 m3
GPS antenna
white diffusion liner
![Page 13: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/13.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 13
1285 tanks deployed … as of February 23/07
1256 with water
1155 with electronics
1600 tanks in total…beginning of2008
![Page 14: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/14.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 14
Auger today
exposition ~ 5000 km2 y srin total ~ 5·105 events104 above 3·1018 eV – fully efficient SD(combined FD + SD …. energy ~ > 3·1017 eV)
photon limit
GC anisotropy
![Page 15: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/15.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 15
Energy reconstruction (zenith < 60 deg)
“MC free” as much as possible
SD measurement calibrated by FD energy
…SD measures S(1000) = signal 1000 m from center - choice of “1000” based on MC . . LDF is measured ! !
…FD – calorimetric measurement of energy - invisible energy estimated by MC
![Page 16: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/16.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 16
Energy . . . . reconstruction
energy reconstruction – S(1000) defined as LDF value 1000 m from impact of shower axis . . . . why 1000 ?
p Fe
![Page 17: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/17.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 17
signal unit ~ 1 VEM
vertical equivalent muon
![Page 18: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/18.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 18
Energy . . . . reconstruction
uncertainty of S(1000) due to signal fluctuation
![Page 19: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/19.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 19
Energy . . . . reconstructionS(1000) of p and S(1000) of Fe …
fluctuations
![Page 20: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/20.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 20
FD versus SDattenuationS(1000) -> S38(1000)
M. Roth, M. Unger, …
Constant Intensity Cut
![Page 21: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/21.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 21
Pierre Auger observatory - FDFD can see up to 25 - 30 kmlaser calibration, atmosphere monitoring, . . .
stereo events -Čerenkov subtraction
![Page 22: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/22.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 22
FD ….. fluorescence yieldexperiment AIRFLY . . .
![Page 23: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/23.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 23
X – differences to US-Std. in III/05
Atmospheric monitoringAtmospheric monitoring
![Page 24: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/24.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 24
![Page 25: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/25.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 25
![Page 26: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/26.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 26
reversal of the standard SD energy reconstruction
check of MC
![Page 27: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/27.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 27
Events
![Page 28: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/28.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 28
Events
![Page 29: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/29.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 29
Lateral Distribution Function Fit
Surface Array view
Core distance (m)
Tan
k s
ign
a l (
VE
M)
Wed Mar 3 15:05:09 2004Easting = 477567 ± 21 m
Northing = 6084561 ± 25 mdt = 92.0 ns
Theta = 63.5 ± 0.1 degPhi = 72.1 ± 0.1/sin(Theta) deg
R = 24.2 ± 0.8 km
S(1000) = 86.46 ± 2.69 VEME = 59.44 EeV ± 3%
(stat. error only)PRELIMINARY
![Page 30: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/30.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 30
PRELIMINARY analysis shows
zenith angle 64º, energy 59 EeV
![Page 31: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/31.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 31
reversal of the standard SD energy reconstruction
check of MC
not enough muons !!!
![Page 32: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/32.jpg)
Muons . . .
direct – fromheavy flavours
indirect – mainly from, K decays
Jan Ridky, ISVHECRI, Pylos, Greece, 6-12 Sept. 2004
![Page 33: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/33.jpg)
Typical high multiplicity event
RUN 107634, EVT 4731
Jan Ridky, ISVHECRI, Pylos, Greece, 6-12 Sept. 2004
![Page 34: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/34.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 34
Events . . . . even more inclined one
B
![Page 35: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/35.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 35
Conclusions:
• Auger – South close to completion (early 2008)
• the technical parameters of PAO will allow unprecedented measurements in terms of statistics (area) energy (size of SD) pointing (FD angular resolution < 1 deg) composition (good atmospheric monitoring) precision (hybrid approach)
• valuable contribution to HEP . . . . in synergy with LHC – MC tuning
![Page 36: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/36.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 36
supporting slides
![Page 37: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/37.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 37
3 PMTs XP1805d1 Photonis read-out• last dynode – 1 FADC• anode – 1 FADC
40 MHz15 bits dynamic range (5 bits overlap)
most frequent signals are those of atmosphericmuons . . . . . . they are used for monitoring and calibration
~ 1 ÷ 1000 particles/μs
![Page 38: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/38.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 38
Trigger T3. . . events
timing of signals(to beat accidentals)
![Page 39: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/39.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 39
Trigger T3. . . events
timing of signals(to beat accidentals)
![Page 40: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/40.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 40
Trigger T3. . . events
~ 0.02 Hz
T3 triggers
• 3ToT . . efficient trigger ~ 90% selected events mostly ‘vertical’ showers
• 4-fold coincidence of tanks within 6 km - essential for horizontal showers, more noisy
![Page 41: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/41.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 41
Trigger T3. . . events
- 3ToT - 4C1
![Page 42: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/42.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 42
Triggering events
trigger probability of a single tank - measured by a pair of close tanks
![Page 43: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/43.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 43
Triggering events
- Threshold or ToT
- Threshold only
1018 eV
1020 eV
![Page 44: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/44.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 44
T3 0 : 30 : 98% for 1 : 3 : 10 EeV zenith angle < 45°
Triggering events
LTP and LDF deduced from experiment by means of close tanks
NKG formula
![Page 45: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/45.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 45
Events
![Page 46: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/46.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 46
Events
![Page 47: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/47.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 47
Events
![Page 48: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/48.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 48
Events . . . . reconstructionuncertainty of S(1000) due to core location
![Page 49: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/49.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 49
Events . . . . reconstructionuncertainty of S(1000) due to missing tank
![Page 50: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/50.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 50
Events . . . . reconstruction
uncertainty of S(1000) due to: • statistical uncertainties at S(1000) ~ 30 VEM this corresponds to ~ 5·1018 eV are ~ 10%• due to LDF form < 4%• due to shower to shower fluctuations ≤ 10%• event sampling (missing tank ≤ 10%)
at ~ 3·1018 eV the surface array fully efficient-trigger efficiency, pressure & temperature dependence
![Page 51: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/51.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 51
1.5 km
1.5 km
![Page 52: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/52.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 52
Pierre Auger observatory - FD
diaphragm
filter 300 - 400 nm
mirror
fail-safe curtain
camera - 20 x 22photomultipliers 2,6”
![Page 53: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/53.jpg)
Saturated event
… we have 6 such cases
Jan Ridky, ISVHECRI, Pylos, Greece, 6-12 Sept. 2004
![Page 54: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/54.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 54
Photon limit
![Page 55: Pierre AUGER Observatory Jan Ridky Institute of Physics AS CR ridky@fzu.cz For Pierre Auger collaboration](https://reader035.vdocument.in/reader035/viewer/2022062805/5697bfdb1a28abf838cb0a13/html5/thumbnails/55.jpg)
Lake Tahoe, 27.2.2007 J. Ridky, C2CR07 55
Photon limit