2007/07/18 by Takahisa Yamamoto, Yamamoto, T.
Earth and Planetary Sciences · Engineering · #Astrophysics (astro-ph) #FOS: Physical sciences #Geophysics and Gravity Measurements #Particle Accelerators and Free-Electron Lasers #Particle accelerators and beam dynamics
paper · pdf · doi:10.48550/arxiv.0707.2638
openalex publication_date 2007/07/18 · openalex created_date 2020/04/10 · openalex updated_date 2026/07/28
The Southern part of the Pierre Auger Observatory is nearing completion, and has been in stable operation since January 2004 while it has grown in size. The large sample of data collected so far has led to a significant improvement in the measurement of the energy spectrum of UHE cosmic rays over that previously reported by the Pierre Auger Observatory, both in statistics and in systematic uncertainties. We summarize two measurements of the energy spectrum, one based on the high-statistics surface detector data, and the other of the hybrid data, where the precision of the fluorescence measurements is enhanced by additional information from the surface array. The complementarity of the two approaches is emphasized and results are compared. Possible astrophysical implications of our measurements, and in particular the presence of spectral features, are discussed.