1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with...
-
date post
22-Dec-2015 -
Category
Documents
-
view
218 -
download
0
Transcript of 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with...
![Page 1: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/1.jpg)
1
Roma Meeting: June 2007
Recent results from the Pierre Auger Observatory
(and comparisons with AGASA and HiRes)
Alan Watson
University of Leeds
![Page 2: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/2.jpg)
2
Czech Republic
France
Germany
Italy
Netherlands
Poland
Portugal
Slovenia
Spain
United Kingdom
Argentina
Australia
Brasil
Bolivia*
Mexico
USA
Vietnam*
*Associate Countries
~300 PhD scientists from
~70 Institutions and 17 countries
The Pierre Auger Collaboration
Aim: To measure properties of UHECR with unprecedentedstatistics and precision – necessary even if no disagreement
![Page 3: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/3.jpg)
3
Array of water-Cherenkov or scintillation detectors
Fluorescence in UV →
11
Shower Detection Methods
OR
300 – 400 nm
Nitrogen fluorescence
The Design of the Pierre Auger Observatory marries these two well-established techniques
AND
~1°
Due to Enrique Zas
![Page 4: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/4.jpg)
4
Present situation Present situation (April 13, 2007)(April 13, 2007)
1410 (1357 filled) SDstations deployed with 1304 taking data (300507) OVER 80%All 4 fluorescence buildings complete,each with 6 telescopes
AIM: 1600 tanks
30 May 2007
![Page 5: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/5.jpg)
5
GPS Receiverand radio transmission
![Page 6: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/6.jpg)
6
UV optical filter(also: provide protectionfrom outside dust)
Camera with 440 PMTs (Photonis XP 3062)
Schmidt Telescope using 11 m2 mirrors
![Page 7: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/7.jpg)
7
θ~ 48º, ~ 70 EeV
Flash ADC tracesFlash ADC traces
Lateral density distribution
Typical flash ADC trace
at about 2 km
Detector signal (VEM) vs time (µs)
PMT 1
PMT 2
PMT 3
-0.5 0 0.5 1.0 1.5 2.0 2.5 3.0 µs
18 detectors triggered
![Page 8: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/8.jpg)
8
Lateral density distribution
θ~ 60º, ~ 86 EeV
Flash ADC traces
Flash ADC Trace for detector late in the shower
PMT 1
PMT 2
PMT 3
-0.5 0 0.5 1.0 1.5 2.0 2.5 3.0 µs
35 detectors triggered
Much sharper signalsthan in more vertical events leads toν- signature
![Page 9: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/9.jpg)
9
79 degrees
![Page 10: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/10.jpg)
10
Laser Facilities Laser Facilities (April 13, 2007)(April 13, 2007)30 May 2007
There are also2 laser facilities,CLF and XLF
Steerable YAG lasersto mimic 100 EeV
CLF
XLF
![Page 11: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/11.jpg)
11
The Central Laser Facility of the Pierre Auger Observatory
355 nm, frequency tripled, YAG laser, giving < 7 mJ per pulse: GZK energy
![Page 12: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/12.jpg)
12
Atmospheric Monitoring
Balloon probes (T,p)-profiles
LIDAR at each FD building
light attenuation lengthAerosol concentration (Mie scattering)
steerable LIDAR facilities located at each FD eye
• LIDAR at each eye
• cloud monitors at each eye
• central laser facility
• regular balloon flights
![Page 13: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/13.jpg)
13
Pixel geometryshower-detector plane
Signal and timingDirection & energy
FD reconstruction
![Page 14: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/14.jpg)
14
ti
Geometrical Reconstruction
![Page 15: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/15.jpg)
15
Angular and Spatial Resolution from Central Laser Facility
Laser position – Hybrid and FD only (m)Angle in laser beam /FD detector plane
Mono/hybrid rms 1.0°/0.18° Mono/hybrid rms 570 m/60 m
![Page 16: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/16.jpg)
16
ARRIVAL DIRECTION DISTRIBUTION FROM AUGER
• No significant emission from Galactic Centre
• No broadband signals – e.g. Dipole – at any energy above 1 EeV e.g 1 < E < 3 EeV, Amplitude < 0.7%
• No clustering of the type claimed by AGASA
• No signal from BL Lacs as possibly seen by HiRes
Summary:Previous Claims have not been confirmed
BUT, two ‘prescriptions’ are currently being tested – but I cannot tell you what they are
![Page 17: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/17.jpg)
17
Energy Determination with Auger
The detector signal at 1000 m from the shower
core
– S(1000)
- determined for each surface detector event
S(1000) is proportional to the primary energy
The energy scale is determined from the data and does not depend on a knowledge of interaction models or of the primary composition – except at level of few %.
Zenith angle ~ 48º
Energy ~ 70 EeV
![Page 18: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/18.jpg)
18
A Hybrid Event
![Page 19: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/19.jpg)
19
S38 vs. E(FD)
387 hybrid events
Absolute value of FDcalibration uncertain ~ 14%
Nagano et al, FY used
![Page 20: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/20.jpg)
20
10 EeV S(1000)
Precision of S(1000) improvesas energy increases
![Page 21: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/21.jpg)
21
![Page 22: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/22.jpg)
22
(Outdated) Summary of FD systematic uncertainties
%
Note: Activity on several fronts to reduce these uncertainties
(to be updated)
~ 14%
![Page 23: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/23.jpg)
23
Summary of systematic uncertainties
Note: Activity on several fronts to reduce these uncertainties
New version from Bruce Dawson’s Merida talk
![Page 24: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/24.jpg)
24
![Page 25: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/25.jpg)
25
5165 km2 sr yr ~ 0.8 full Auger year
Exp Obs>1019.6 132 +/- 9 58
> 1020 30+/- 2.5 2
Spectrum from Surface Detectors
![Page 26: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/26.jpg)
26
Ankle? Comparisons of residualsagainst an arbitrary spectrum
![Page 27: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/27.jpg)
27
Spectrum from very inclined events
![Page 28: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/28.jpg)
28
Calibration curve for Inclined showers
![Page 29: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/29.jpg)
29
Energy Spectrum from 60 °< < 80°: 734 events
1510 km2 sr yr
![Page 30: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/30.jpg)
30
Blue: < 60°Black: inclined
![Page 31: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/31.jpg)
31
ti
A ‘hybrid’ spectrum
![Page 32: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/32.jpg)
32
Triggering probability for Hybrid Events
![Page 33: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/33.jpg)
33
Lunar Cycles
![Page 34: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/34.jpg)
34
Hybrid Spectrum: clear evidence of the ‘ankle’ at ~ 4 x 1018 eV
-3.1 +/- 0.2
![Page 35: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/35.jpg)
35
![Page 36: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/36.jpg)
36
Energy Estimates aremodel and mass dependent
Takeda et al. ApP 2003
Surface Detectors
Recent reanalysis has reduced number > 1020 eVto 6 events
![Page 37: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/37.jpg)
37
Teshima: Roma 2006
![Page 38: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/38.jpg)
38HiRes Group: astro-ph/0703099
- 5.1 +/- 0.7
![Page 39: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/39.jpg)
39
17.0 17.5 18.0 18.5 19.0 19.5 20.0 20.51E-38
1E-37
1E-36
1E-35
1E-34
1E-33
1E-32
1E-31
1E-30
1E-29
1E-28
1E-27
J (
m2 s
r s e
V)-1
log E (eV)
Auger Combined HiResI HiResII
![Page 40: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/40.jpg)
40
18.0 18.5 19.0 19.5 20.0 20.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5(J
/Js )
- 1
log E (eV)
Auger HiRes I HiRes II
x3
x2
x1
Plot of residuals of individual spectra compared to standard, Js = A E-2.6
![Page 41: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/41.jpg)
41
Immensely important IF it was to be establishedthat slopes at highest energy are different in northern (- 5.1+/- 0.7) and southern hemispheres (- 4.1 +/- 0.4)
But, MUCH TOO EARLY TO DRAW CONCLUSIONS
• Uncertainties about HiRes aperture
• Poorer energy and angular resolution in HiRes than Auger
• Low number of events – and no more to come to from HiRes
• Issue will be addressed with more Auger data
![Page 42: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/42.jpg)
42
The HiRes aperture is noteasy to compute and requiresassumptions about the spectral indexand the mass composition in regionswhere it has not been measured.
astro-ph/0703099
Physics Letters B 2005
![Page 43: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/43.jpg)
43
Exposure
AGASA ~1700
HiResI “3-4 times AGASA”
Auger
6675
1019 0.49 0.29 0.22
827 564 1473
> 4 x 1019 0.04 0.015 0.10
65 49 66
> 7x 1019 0.014 3.6 x 10-3 2 x 10-3
24 13 13
> 1020 6 x 10-3 1.0 x 10-3 3 x 10-4
11 4 2
Integral Rates: km-2 yr-1 sr-1
![Page 44: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/44.jpg)
44
Variation of Depth of Maximum with Energy
Inferring the Primary Mass: Crucial for Interpretation
******
******
******
******
Xmax
log E
p
Fe
Key is energy per nucleon
protonsnucleineutrinosphotons
all are expected at some level- at different energies
![Page 45: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/45.jpg)
45
![Page 46: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/46.jpg)
46Fluctuations in Xmax yet to be explored and exploited
Elongation Rate measured over 2 decades in energy
![Page 47: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/47.jpg)
47
and few photons at high energy
AnkleFluctuations in Xmax to be exploited
![Page 48: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/48.jpg)
48
![Page 49: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/49.jpg)
49Jump to 66
![Page 50: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/50.jpg)
50Berezinsky et al Phys Rev D 74 (2006)
Steepening affected by over- and under-densities
Comparison of data with models of origin and propagation
Berezinsky et al. argue that the dip is caused by γ + p p + e+ + e-
![Page 51: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/51.jpg)
51
![Page 52: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/52.jpg)
52
Knee
>1019 eV1 km-2 sr-1 year-1
air-showers
after Gaisser
Hadronic Physics
Ankle
![Page 53: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/53.jpg)
53
Models describe Tevatron data well - but LHC model predictions reveal large discrepancies in extrapolation.
Could there be surprises in the hadronic physics?
James L. Pinfold IVECHRI 2006 13
ET (LHC)
E(LHC)
![Page 54: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/54.jpg)
54 Prospects from LHCf
![Page 55: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/55.jpg)
55
LHC measurement of TOT expected to be at the
1% level
– useful in the extrapolation up to UHECR energies
The p-p total cross-section
10% difference in measurements ofTevatron Expts:
James L. Pinfold IVECHRI 2006 14
(log s)
![Page 56: 1 Roma Meeting: June 2007 Recent results from the Pierre Auger Observatory (and comparisons with AGASA and HiRes) Alan Watson University of Leeds a.a.watson@leeds.ac.uk.](https://reader031.fdocuments.net/reader031/viewer/2022020219/56649d7e5503460f94a61dd6/html5/thumbnails/56.jpg)
56
Summary:• Spectrum: ankle and steepening seen in model-
independent measurement and analysis
• But what does this all mean? Is the ankle marking a galactic/extra-galactic change?
Have we seen the GZK effect?Or is it a ‘bump’ from a more local effect?Are the accelerators just ‘tired’?
Can we deduce much from propagation models?
• Measuring MASS is crucial: mixed at highest energy?
• Need a point source (or some evidence of anisotropy) – and/or more insight about hadronic interactions