2001/12/20 by A. A. Watson, Watson, A. A.
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0112474
8 pages, 2 figures, Invited paper presented at "Frontiers of the Universe", 17th - 23rd June 2001, XIII Rencontres de Blois
arxiv created 2001/12/20 · arxiv updated 2009/12/01
Reasons for the current interest in cosmic rays above 1019 eV are described. The latest results on the energy spectrum, arrival direction distribution and mass composition of cosmic rays are reviewed, including data that were reported after the meeting in Blois in June 2001. The enigma set by the existence of ultra high-energy cosmic rays remains. Ideas proposed to explain it are discussed and progress with the construction of the Pierre Auger Observatory is outlined.