出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：Recent results obtained with the Pierre Auger Observatory are described. These include measurements of the spectrum, anisotropies and composition of ultra-high energy cosmic rays. The ankle of the spectrum is measured at 4×1018 eV and a suppression above 3×1019 eV consistent with the GZK effect is observed. At energies above 5.5×1019 eV a correlation with the distribution of nearby extragalactic objects is found, including an excess around the direction of Centaurus A, the nearest radio loud active galaxy. Measurements of the depth of shower maximum and its fluctuations suggest a gradual change in the average mass of the primary cosmic rays (under standard extrapolations of hadronic interaction models), being the results consistent with a light composition consisting mostly of protons at few×1018 eV and approaching the expectations from iron nuclei at 4×1019 eV. Upper bounds on the photon fraction and the neutrino fluxes are also obtained.
