pierre auger observatory. pierre auger(1899-1993) was a nuclear physics and cosmic ray physics. made...
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Pierre Auger Observatory
Pierre Auger(1899-1993)
• Was a nuclear physics and cosmic ray physics.
• Made cosmic ray experiments on the Jungfraujoch
• Discovery of extensive air showers (1938)• He estimated the energy to 1015 eV
Location of the auger experiment
Involved countries
http://www.auger.org/collaboration/
Aim of the experiment
• Measure the energy spectrum of high energy cosmic rays up to energies of 1020 eV
• Determine the direction of these cosmic rays
• Determine the element composition of cosmic rays
• Study of extensive air showers
The experiment
• Detector field: 3000 km2
• 24 Fluorescence cameras on 4 observations points
• 1600 Surface detectors (1.5 km spacing)
Fluorescence detector• Charged particles in
an air shower also interact with atmospheric nitrogen (excitation)
• Emitted ultraviolet light via a process called fluorescence
• Direction and energy of the cosmic particle can be determined
Fluorescence detector
Spiegel (links) und Kamera (rechts) eines Fluoreszenzteleskops.
Surface detector
Surface detector• Base of detector = 10m2
• 12 tons of very pure water as detection material
• 3 Photomultipliers detect cerenkov signals
• With GPS antenna high time correlation to different detectors
• Energy given in VEM (Vertical Equivalent Muon)
Cerenkov radiation
• Speed of the particle must be higher than the speed of light in the medium
• Speed of light in water = 0.75c
Combination of FD and SD
Results
Results
Results
Abb. 1: Korrelation zwischen der kalorimetrischen Energiemessung durch die Fluoreszenzmessung und dem Energieschätzer S38° des Detektorfeldes.
Results
Correlation
Red stars: Quasars or active galactic nucleiCircles: High energy cosmic rays more than 57EeV
Correlation
• Rejected the hypothesis of isotropic distribution of cosmic rays above 6 x 1019 eV
• Very high cosmic particles have extragalactic origin
• Higher flux of cosmic particles from the galactic centers and Quasars
Eventdisplay und Animationen
Status and planned upgrades
• Increase the density of the surface detectors to get a better study of low energy cosmic rays (1015 eV)
• Detection of extended air showers with radio antennas
• Realization of the Auger detector at the northern hemisphere (Colorado)
Auger nord
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