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Cosmic Rays above the Knee
Michael Unger
An overview on the present observational status and phenomenological understanding of cosmic rays above 10^16 eV is given. Above these energies the cosmic ray flux is expected to b…
Reconstruction of Longitudinal Profiles of Ultra-High Energy Cosmic Ray Showers from Fluorescence and Cherenkov Light Measurements
M. Unger, B. R. Dawson, R. Engel +2
We present a new method for the reconstruction of the longitudinal profile of extensive air showers induced by ultra-high energy cosmic rays. In contrast to the typically considere…
Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei
The Pierre Auger Collaboration
Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest energies, which are correlated with the…
On the measurement of the proton-air cross section using cosmic ray data
Ralf Ulrich, Johannes Bluemer, Ralph Engel +2
Cosmic ray data may allow the determination of the proton-air cross section at ultra-high energy. For example, the distribution of the first interaction point in air showers reflec…
On the relation between the proton-air cross section and fluctuations of the shower longitudinal profile
R. Ulrich, J. Blümer, R. Engel +2
The current status and prospects of deducing the proton-air cross section from fluorescence telescope measurements of extensive air showers are discussed. As it is not possible to…
Study of the Cosmic Ray Composition above 0.4 EeV using the Longitudinal Profiles of Showers observed at the Pierre Auger Observatory
Michael Unger
The Pierre Auger Observatory has been collecting data in a stable manner since January 2004. We present here a study of the cosmic ray composition using events recorded in hybrid m…
On the measurement of the proton-air cross section using longitudinal shower profiles
Ralf Ulrich, Johannes Blümer, Ralph Engel +2
In this paper, we will discuss the prospects of deducing the proton-air cross section from fluorescence telescope measurements of extensive air showers. As it is not possible to ob…
Validation of the Real and Simulated Data of the Pierre Auger Fluorescence Telescopes
The Pierre Auger Collaboration, L. Perrone
The fluorescence detector (FD) of the Pierre Auger Observatory is currently operating 18 fluorescence telescopes of the 24 that will be employed in the completed detector. These te…
Atmospheric Profiles at the Southern Pierre Auger Observatory and their Relevance to Air Shower Measurement
B. Keilhauer, J. Bluemer, R. Engel +8
The dependence of atmospheric conditions on altitude and time have to be known at the site of an air shower experiment for accurate reconstruction of extensive air showers and thei…