Hadronic interactions: From LHC to Ultra-High Energy Cosmic Rays

• Applicant: Dr. Sergey Ostapchenko, Ph.D.
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields ; Astrophysics and Astronomy ; Theoretical Chemistry: Molecules, Materials, Surfaces
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 252403571

The interpretation of high energy cosmic ray data and the solution of the enigma of the origin of ultra-high energy cosmic rays depend crucially on the validity of hadronic Monte Carlo models which are required for the description of the interactions of cosmic ray particles in the atmosphere. The project is aimed at the further development of a modern hadronic Monte Carlo generator, taking the full advantage of new theoretical approaches and of existing and forthcoming accelerator data. Core element of this improved Monte Carlo generator is the implementation of a self-consistent treatment of hadronic and nuclear collisions, based on the perturbative description of nonlinear interaction effects related to multi-parton interactions, into the existing QGSJET-II model. The model will be thoroughly tested and calibrated with relevant accelerator data, notably, from the Large Hadron Collider. It will be applied to the calculations of characteristics of cosmic ray induced extensive air showers. The results will be compared to experimental data of the Pierre Auger Observatory and conclusions on the nuclear composition of the ultra-high energy cosmic ray flux will be drawn. The interdisciplinary aspect of the project is twofold: First, modern theoretical approaches and accelerator data will be used to develop a reliable tool for high energy cosmic ray studies. Secondly, the developed model will have a vast range of applications in collider physics, e.g. in relation to studies of general minimum bias collisions in hadronic and nuclear interactions, soft and hard diffraction, and multi-parton interactions.

• DFG Programme: Research Grants
• Co-Investigators: Professor Dr. Marcus Bleicher, Ph.D.; Dr. Tanguy Pierog, Ph.D.