1. Pierre Auger Observatory Present and Future
Ruben Conceição
Jornadas LIP 2010 – Braga

2. Extensive Air Showers (EAS)
Cosmic ray spectrum
Ultra High Energy Cosmic Rays
What are they?
Where do they come from?
What can we learn with them?
Rare events
Impossible to detect directly
Interact with Earth’s atmosphere creating huge particle showers
Tevatron (p-p)
LHC (p-p)

3. Pierre Auger Observatory
The Auger Observatory is a "hybrid detector," employing two independent methods to detect and study high-energy cosmic rays:
Surface detector (SD)
3000 km2 in the Pampa Argentina
1600 pure water tanks
Fluorescence Detector (FD)
4 “eyes” each with 6 telescopes
Several systems to monitor the atmosphere
Auger is now completed
Very high statistics up to 50 EeV
Above 50 EeV we get 30 events per year

4. Energy Spectrum FD
Lower energy range SD
higher exposure
Enough statistics to see GZK cut-off like feature

5. UHECR Propagation GZK cut-off effect
Interaction with CMB photons degrades energy
Sources must be nearer than 100 MPc
Magnetic fields don’t bend very high energy particles
Charged Particle Astronomy!!
Access Galactic and Extra-Galatic magnetic fields

6. Where do they come from? Top energy CR data is anisotropic!!
CR energy above 55 EeV
Probability of being isotropic is less than 1%
Some correlation with AGN distribution is observed
The small deviation from AGNs suggests that the particle is a proton?!

7. What are they? Elongation Rate
<Xmax> as a function of the primary energy
Iron  56 nucl (E/56)
Smaller fluctuactions
Smaller Xmax
Data goes to a heavier composition as energy increases
But elongation rate is also sensitive to hadronic models
p-Air Cross-Section
Muon excess seen from SD!!!
Anisotropy
Proton
Iron
Data
Anisotropy

8. Also a gamma and neutrino detector!!
Photons
Neutrinos
No candidate found yet!!

9. Next steps… Fully explore the data Reduce systematic uncertainty
Auger South Enhancements
Auger North

10. Auger South Enhancements
Extension to lower energies
High Elevation Auger Telescopes
Upgrades
Present
2nd knee
Ankle
AMIGA detectors
Auger Muons and Infill for the Ground Array
Study muon component of showers
Good variable to check hadronic models

11. Auger North Colorado, USA
Increase the statistics of very high energy events
200 events/year above 55 EeV
4000 tanks over km2
39 FD telescopes in 5 stations
Enables full-sky exposure

12. Conclusions
Auger South is completed and has already given important results
GZK like suppression
Highest energy events are anisotropic
Puzzling scenario: composition change or new physics
Further improvements will come from higher statistics and a better control of systematics
Auger North will provide a full sky coverage and an important increase on statistics for the highest energy events

13. Thank you!!

14. Backup slides

15. Pierre Auger Observatory
The Auger Observatory is a "hybrid detector," employing two independent methods to detect and study high-energy cosmic rays:
Surface detector (SD)
3000 km2 in the Pampa Argentina
1600 pure water tanks
1.5 km spacing
Flourescence Detector (FD)
4 “eyes”
6 telescopes in each viewing 30o x 30o
4 weather stations (with LIDARs)
2 Laser Facilities FD SD
Auger is now completed
Very high statistics up to 50 EeV
Above 50 EeV we get 30 events per year

16. Event Reconstruction Surface Detector Fluorescence Detector
Tank hit time gives shower direction
Energy is obtained using
Nch( distance to the shower core )
Evolution in camera gives the shower geometry
Energy is calculated by integrating a universal longitudinal profile

17. Hybrid Technique Better reconstruction geometry
Higher Xmax resolution
Better energy reconstruction
Calibration of SD with FD
Reduce systematics
Good correlation between SD and FD SD FD

18. Auger North Expands Auger aperture eight-fold for E>55 EeV
4000 tanks
2.28 km spacing
km2
Enables full-sky exposure
200 events/year instead of 25 events/year
Enables Xmax studies above 55 EeV
39 FD telescopes in 5 stations