Southeastern Colorado Selected for International Cosmic Ray Observatory

$50 million Observatory Project

The Pierre Auger Observatory, an international collaboration of astrophysics researchers, has selected an area in southeastern Colorado as the site for their Northern Hemisphere observatory. The observatory - an array of tanks of water - will complement the similar Auger Southern Hemisphere observatory now nearing completion in Argentina.

After several site visits by representatives of the international collaboration, the Auger Collaboration voted June 7, 2005, to select the site in Baca, Bent, and Prowers Counties. The Colorado site met the scientists' criteria of flat, open spaces; clear dark skies; and good access to the planned array of detectors with room to expand to an even larger scale if future scientific developments warrant.

A team led by Prof. John Harton and Dr. Pablo Bauleo of Colorado State University documented the atmospheric conditions and coordinated the Colorado presentation. Local officials from Baca, Bent, and Prowers Counties, through the Southeast Colorado Enterprise Development (SECED) organization, coordinated support from the local communities and solicited agreements from area farmers and ranchers to allow the detector tanks to be placed on their property.

In addition, the Auger project's visitor center and offices will be located on land donated by Lamar Community College. At the state level, the Colorado Economic Development Commission and the Department of Local Affairs agreed to provide financial support for these efforts. The Colorado General Assembly passed a unanimous resolution of support, HJR 04-1033 (Sen. Ken Kester and former Rep. Brad Young). CSU administration is also enhancing the university's High Energy Physics faculty and laboratories to support its commitment to the Auger project and other upcoming research initiatives.

The Pierre Auger Collaboration is a group of some 250 physicists from 50 institutions in 13 countries. It has designed the observatories to study the universe's highest energy particles. These sub-atomic particles carry energy levels that cannot be explained by any known sources, such as exploding stars.

Because the high-energy particles being studied are so rare, the Auger Observatory is designed to detect particles falling anywhere over an area the size of Rhode Island. The observatory consists of an array of some 1,600 particle detectors spaced approximately one mile apart within an approximately 35 mile by 35 mile area. The detectors are small tanks of purified water that are completely dark except for traces of light left when struck by cosmic ray particle showers. Auger will record enough events, and with enough precision, to draw the first detailed map of the sources of these ultra-high-energy particles.

The budget for building the complex of detectors is about $50 million, to be funded by the U.S. Department of Energy Office of Science, the National Science Foundation, and scientific research organizations in other participating countries. A fact-finding mission from southeastern Colorado to Argentina found that in addition to bringing many visitors to the area, the project created several permanent jobs managing the facilities, as well as construction and installation over several years. The delegation also discovered a number of other intangible benefits, such as participation by Project personnel as volunteers in science education in the local schools.

For more information on the Auger project and cosmic rays, visit: