Skip to main content
Article thumbnail
Location of Repository

Physical Review Letters

By J. Abraham, P. Abreu, M. Aglietta, E. J. Ahn, D. Allard, I. Allekotte and J. Allen


p. 1-7We describe the measurement of the depth of maximum, Xmax⁡, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 1018  eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106-21+35)  g/cm2/decade below 1018.24±0.05  eV, and (24±3)  g/cm2/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26  g/cm2. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed

Year: 2010
OAI identifier:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.