PoS - Proceedings of Science
Volume 301 - 35th International Cosmic Ray Conference (ICRC2017) - Session Cosmic-Ray Indirect. CRI-properties of CRs at high energies (anisotropy, energy, mass)
$<X_{max}>$ measurements and tests of hadronic models using the surface detector of the Pierre Auger Observatory
P. Sanchez-Lucas*  on behalf of the Pierre Auger Collaboration
Full text: pdf
Pre-published on: August 16, 2017
Published on: August 03, 2018
The time structure of the signals from air showers, recorded with the water-Cherenkov detectors of the Pierre Auger Observatory, contains information that can be related to the mass composition of primary cosmic rays and to hadronic multi-particle production. We can study both because the recorded signals contain a mix of the muonic and electromagnetic components. Using information from the time structure, we define observables that enable a comparison of observations with predictions from hadronic models. We have found that the interpretation obtained from a comparison of our data to these predictions is inconsistent with the interpretation obtained by comparing fluorescence measurements and model predictions, over a greater energy range, and with higher precision, than in previous studies. Information about mass composition is obtained by calibrating the observables based on time structure with fluorescence measurements. Following this approach, we infer the depth of shower maximum, Xmax, from 0.3 EeV to over 100 EeV. In particular, above 30 EeV, our sample is nearly fourteen times larger than currently available from fluorescence measurements. With this novel approach we find good agreement with previous studies and, with our larger sample, we have extended the measurement of <Xmax> to greater energies than
DOI: https://doi.org/10.22323/1.301.0495
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.