Monte Carlo Simulations and Computing activities for the Pierre Auger Observatory

by Alexey Yushkov (FZU), Eva Martins dos Santos (FZU)

Tuesday 7 May 2024, 16:15 → 17:15 Europe/Berlin

ENC-D308

The Earth is constantly bombarded by cosmic rays, arriving primarily from extra-solar and, at the highest energies, extra-galactic astrophysical sources. However, for energies above 10^{^15} eV, cosmic rays may only be detected indirectly through the many millions of secondary particles generated in a cascading process triggered by the interaction of a cosmic ray in the Earth's atmosphere. In the latter, the inference on the nature of the detected cosmic rays relies on Monte Carlo simulations describing the high-energy hadronic interactions in the extensive air showers and detailed detector simulations. At the highest energies, the simulation of such extensive air showers becomes computationally expensive, and algorithms to reduce the computation time and disk space are mandatory. 
The Pierre Auger Observatory, located in the province of Mendoza, Argentina, is the world's largest cosmic ray detector. In stable operation since 2004, it has provided numerous breakthrough results about the nature and origin of the most energetic particles in the Universe. Its hybrid design comprises an array of 1660 water-Cherenkov detectors with a fluorescence detector (FD) composed of 27 fluorescence telescopes deployed at the array periphery, overlooking the area above the surface detector (SD) array. In this seminar, our production framework of reference extensive Monte Carlo libraries of air-shower and detector simulations for a wide range of analyses conducted by the Pierre Auger Collaboration is given. We will focus on the Monte Carlo code CORSIKA - COsmic Ray SImulations for KAscade, used to produce detailed simulations of extensive air showers in the Earth's atmosphere, using from protons to most heavy nucleons as primary particles, including high- and ultra-high-energy photons and neutrinos. Finally, we will explain how we use the Auger Offline Framework software to simulate and reconstruct the CORSIKA extensive air shower simulations as real events.