https://doi.org/10.1051/epjconf/201713602002
Astrophysical interpretation of Pierre Auger Observatory measurements of the UHECR energy spectrum and mass composition
1 INFN and Department of Physical and Chemical Sciences, University of L’Aquila, L’Aquila, Italy
2 Observatorio Pierre Auger, Av. San Martín Norte 304, 5613 Malargüe, Argentina
a e-mail: armando.dimatteo@aquila.infn.it
b Now at Service de Physique Théorique, Université Libre de Bruxelles, Brussels, Belgium
c e-mail: auger_spokespersons@fnal.gov
d Full author list: http://www.auger.org/archive/authors_2016_06.html
Published online: 23 March 2017
We present a combined fit of a simple astrophysical model of UHECR sources to both the energy spectrum and mass composition data measured by the Pierre Auger Observatory. The fit has been performed for energies above 5 EeV, i.e. the region of the all-particle spectrum above the so-called “ankle”’ feature. The astrophysical model we adopted consists of identical sources uniformly distributed in a comoving volume, where nuclei are accelerated with a rigidity-dependent mechanism. The fit results suggest sources characterized by relatively low maximum injection energies and hard spectral indices. The impact of various systematic uncertainties on the above result is discussed.
© The Authors, published by EDP Sciences, 2017
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
