Study of Highest Energy Cosmic Rays

University Of Chicago, Chicago IL

Investigators

Abstract

This proposal requests support for a University of Chicago group for its participation in the construction of the Pierre Auger Observatory. The Pierre Auger Observatory, when completed, is intended to consist of two cosmic ray detectors, one presently under construction in Malargue Argentina, and the other eventually to be in Utah. Each observatory will consist of an array of 1600 particle detectors based on detecting Cherenkov light spread over 3000 square kilometers complements with atmospheric fluorescence detectors. The arrangement is optimized to detect with maximum efficiency showers initiated by primary cosmic rays with energy greater than 1019 electron volts. The southern observatory is being built by a consortium of eighteen nations. The US contribution to the southern $50 million construction project is $7.5 million coming equally from the NSF (PHY-9979239) and the DOE, with an additional $2 million in project support from Fermilab. At the present time an engineering array of 40 surface particle detectors and two fluorescence detectors is nearing completion. This is necessary in order to verify the entire design including the individual detectors, solar power, wireless communications, and GPS timing. The Chicago group has participated in many aspects of the project. The PI is the spokesman for the entire project, and is the PI for the US construction award (9979239) and its DOE counterpart. He has been responsible for the scientific direction of the project. Ken Gibbs has directed the survey for the engineering array, is developing plans for the survey and installation of the full array, and installation of the weather monitoring stations. Brian Fick has developed the weather monitors and is task leader for development of the hybrid software, which combines data from the surface and fluorescence detectors. Paul Sommers is the task leader for the fluorescence detectors.