Pierre Auger Observatory

Hybrid Detector

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The hybrid nature of the Pierre Auger Observatory provides for two independent ways to see cosmic rays. Read More...

Time Lapse Video

Who Was Pierre Auger?

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The Pierre Auger Observatory experiment was named after Pierre Victor Auger (1899 - 1993) Read More...

A world-record sensitivity on the flux of ultrarelativistic magnetic monopoles

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Maxwell’s unified description of electric and magnetic phenomena is one of the greatest achievements of 19th century physics. Free magnetic charges and currents are not allowed in Maxwell’s equations, a consequence of their apparent absence in Nature. However, their existence would naturally explain the quantization of electric charge, as first noted by Dirac in 1931.


Reconstruction of the muon production depth in the atmosphere with the surface detectors of the Pierre Auger Observatory

Cosmic rays are energetic particles, mostly atomic nuclei, raining down upon the Earth from the depths of the cosmos. Understanding their detailed nature and origins remains a primary goal in modern-day astroparticle physics.


Obituary on Jim Cronin by Alan Watson

2016-09-22 Cronin On 21 September 2016 Alan Watson published an obituary on his collegue and friend Jim Cronin on the website of the international weekly journal of science Nature.


First SSD stations deployed in the field

2016-09-15 SSD-Deployment

On Sep. 15, six Surface Scintillator Detector (SSD) stations were deployed with a single trip to the engineering array site. Five more stations are planned to be deployed next week. The photograph shows the first detector set up in the field, which is part of the triplet at the so-called station Generalife.


Memories of James W. Cronin

2016-09-15 Cronin

On the occasion of the celebration of Jim Cronin’s life on September 30, 2016 came up the idea to gather individual recollections and stories [http://astro.uchicago.edu/Cronin/memories.php] about Jim and the Auger Observatory over the years.

Below are some recollections from Paul Mantsch (Scientist Emeritus at Fermilab), former spokesperon of the US Auger Collaboration and close friend to Jim.


James W. Cronin – Founding Father of the Pierre Auger Observatory, 1931-2016


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James W. Cronin (University of Chicago)


The Pierre Auger Collaboration sadly shares the news that James W. Cronin, Professor Emeritus at the University of Chicago and spokesperson emeritus of Auger died on 25 August, at the age of 84.

Born in Chicago, Illinois, on 29 September 1931, graduated with a PhD in physics in 1955, James Cronin shared the 1980 Nobel Prize for Physics with Val Fitch for their 1964 discovery that decaying subatomic particles called K mesons violate a fundamental principle in physics known as "CP symmetry."

After his prizewinning work, he eventually turned his research to cosmic rays and he was a founding father of the Pierre Auger Observatory, the world's largest cosmic-ray detector, which he conceptualized in 1992 with fellow physicist from the University of Leeds Alan Watson.

In his Nobel biographical statement, he emphasized the importance of his family to his career. “On even the worst days, when nothing was working at the lab, I knew that at home I would find warmth, peace, companionship, and encouragement. As a consequence, the next day would surely be better.”

Our thoughts and deepest sympathy go to his family, his wife, children and grandchildren.


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Auger On Site

Shower Simulations

shower simulation

A computer is used to construct a model of what happens in a high energy cosmic ray airshower. Read More...

Google Earth


A model of the Observatory layout was constructed, to be viewed interactively using Google Earth. Read More...

Event Display


The Pierre Auger Collaboration agreed on making 1% of its data available to the public. Read More...