In New Eyes on the Universe there’s a chapter on cosmic rays, and you can find information there on many of the existing and planned cosmic ray detectors. So you can learn about the Pierre Auger Observatory, the Telescope Array Project, JEM-EUSO and lots of others.
But I missed one out.
The Hundred Square km Cosmic ORigin Explorer (HiSCORE – yes, it’s another acronym) is a Russian-German collaboration aimed at learning more about one of the longest-standing puzzles in astrophysics: the source those mysterious cosmic rays with incredibly high energies. When HiSCORE is completed in 2020 it will have 1000 photomultiplier-based detectors spread over a hundred square kilometres of the Tunka Valley near Lake Baikal, Siberia. The intention is to search for Cerenkov radiation generated when ultra-high energy cosmic rays smash into atoms in the Earth’s atmosphere. The HiSCORE team hopes to study cosmic rays with energies up to an EeV (which is, of course, way beyond anything the LHC can produce).
The first prototypes for the observatory are now being installed, which is why HiSCORE is in the news right now. This burst of interest will fade – but keep an eye on the HiSCORE. Perhaps it will help solve the puzzle of how the hell Nature packs macroscopic levels of energy into subatomic particles.