Public PhD Defence: Bridging Monte Carlo Worlds: A New Framework for Accelerator Physics Simulations Applied on Shielding and Machine Protection Studies

by Andre Donadon Servelle (EPFL - Ecole Polytechnique Federale Lausanne (CH))

Friday 3 May 2024, 10:30 → 12:00 Europe/Zurich

6/2-024 - BE Auditorium Meyrin (CERN)

This thesis delves into the critical study of particle transport in matter, particularly emphasising
its implications for machine protection at CERN's accelerator complex and facilities. To conduct
studies of this nature, FLUKA and Geant4 stand out within a small group of general-purpose,
multi-particle Monte Carlo codes, validated in energies reaching the multi-TeV. However, their
structural differences and user interface philosophies present significant challenges in obtaining
results with both codes for the same problems. Overcoming these challenges is crucial, considering
the inherent limitations of MC codes due to their physical models and reliance on specific databases
for particle transport calculations.

A significant contribution of this work is the development of "Moira", a new software that
integrates the infrastructure of Geant4 with the capability to process FLUKA inputs. This novel
Geant4 application allows for a unique comparison of results between the two codes, enabling
simulations with equivalent characteristics, with the primary distinction being the physical models
used.

Using "Moira", this thesis presents a series of simulations using alternative models to FLUKA's, to
analyse shielding and machine protection studies, focusing mainly in scenarios covering sections
that span hundreds of meter in the Large Hadron Collider. Doing these simulations with multiple
physics models permit to obtain a better quantification of the systematic errors, and also contribute
significantly to the development of Monte Carlo codes.