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Pierre Auger Cosmic Ray Observatory

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Research Areas:
NSF Award:

The Highest Energy Astroparticle Physics  (University of Chicago)

Research Focus & Anticipated Benefits

The Pierre Auger Observatory is designed to study the origin and nature of the highest energy particles ever observed, which shower down on Earth in the form of cosmic rays.  The observatory’s southern facility, on the vast plain known as the Pampa Amarilla in western Argentina, is the first hybrid detector to combine two independent techniques for measuring the energy and studying the composition of these particles. One technique detects the particles through their interaction with water in a tank.  The second tracks the development of a cosmic ray shower through ultraviolet light emitted high in the atmosphere. Because the highest energy cosmic rays are extremely rare—with an estimated arrival rate of just one per square kilometer per century—the observatory’s array of 1,600 water-tank particle detectors is spread out over an area about the size of the state of Rhode Island.

The southern facility has been collecting data since 2004, even while construction of the detectors continued.  A matching northern site is slated to be constructed in southeastern Colorado, providing coverage of the skies from both hemispheres.

The discovery of the origin of the highest energy particles would impact both astrophysics and particle physics. Already, scientists using the Auger Observatory have concluded that the source of the highest energy particles is probably associated with active galaxy centers, and that huge black holes may be a source of the activity.

The National Science Foundation supports the construction and operation of the Pierre Auger Observatory through a grant to the University of Chicago.  The U.S. Department of Energy also supports construction and operation of the facility.
NSF also supports researchers across the United States involved in the construction and research projects that use the facility, including teams from the University of Chicago, Ohio State University, Penn State University, University of Nebraska, University of Utah, Case Western Reserve University and Northeastern University.

Education & Outreach

The southern Pierre Auger Observatory in Argentina has conducted programs in public education and outreach in participating countries around the globe and has publicly released a portion of the cosmic ray data it has collected. The observatory staff has contributed to local education in western Argentina through tours, talks in schools, and support of local school programs.

Research teams from a number of universities across the United States involve graduate students, undergraduates, and even high school students and teachers in hands-on research projects using the observatory and the data it collects. The University of Chicago—in collaboration with the Auger Visitors Center, the Malargue Planetarium, and Chicago’s Adler Planetarium—also conducts public science education and outreach by developing and promoting 3-D and 2-D visualizations of cosmic ray showers, detection methods, and possible sources of the particles.

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  • view of Pierre Auger observatory