Background Processes Affecting the Machine-Detector Interface at FCC-ee With Focus on Synchrotron Radiation at 182.5 Gev Beam Energy

Synchrotron radiation is a significant background source at circular lepton colliders. The current interaction region (also referred to as Machine-Detector Interface) design concept at FCC-ee includes only a very basic estimate of this background source. Collimators – as flexible mitigation method of the photon background – are not part of the design yet. This thesis provides a detailed overview on expectable synchrotron radiation backgrounds, also looking into the impact of different machine conditions. Current design concepts for mitigation are tested, at the same time giving an initial collimation proposal to improve machine and detector protection. By employing extensive Monte-Carlo simulations, it is possible to characterize the current status and to show which circumstances allow additional upstream collimators to significantly enhance the shielding of the interaction region. The findings of this thesis can be used to improve the machine-detector interface layout and help as a starting step towards a possible FCC-ee technical design.