Abstract: More than 50 years ago, a new technique that allows the “visualization” of particle cascades produced by extremely energetic cosmic rays was developed. This allowed, for the first time, a calorimetric measurement of cosmic ray energies above 1017 eV to the highest energies, by using air-fluorescence. The original proof-of-concept detector, dubbed “The Fly’s Eye”, was designed and built by physicists from the University of Utah and operated from 1983 to 1994. I will describe how this came about, and the further expansion of the idea into the High Resolution Fly’s Eye and the Auger and Telescope Array experiments. I will then describe the evolution of our understanding of this enigmatic radiation, from our first naïve “particle-physicist” expectations of simplicity, to the current astrophysical stew (“nullum beneficium impunitum”).
The Yodh Prize recognizes a scientist whose research career has had a major impact on the understanding of cosmic rays. It was endowed by Gaurang and Kanwal Yodh to the University of California Irvine Foundation in 1998.
The recipient is selected by an international committee of distinguished scientists in the field of cosmic rays and astroparticle physics. The award is administered through the Commission on Astroparticle Physics of the International Union of Pure and Applied Physics (IUPAP) and is presented every two years at the International Cosmic Ray Conference. In addition, the prize winner presents a Colloquium to the Department of Physics and Astronomy at UC Irvine.