AI-Enhanced Muon Shield Design for Background Mitigation in Next-Generation Intensity Frontier Experiments at CERN

The North Area at CERN uses a 400 GeV/c proton beam from the SPS to supply secondary beams to fixed-target experiments. Among these, K12 supports NA62, a precision experiment studying ultra-rare Kaon decays. With NA62 concluding after CERN's Run~3, the beamline to Experimental Cavern North 3 (ECN3) will become available, offering an opportunity for new experiments -HIKE with SHADOWS and NaNu or SHiP with SND@SHiP - to search for physics beyond the Standard Model. This thesis presents studies that were essential in demonstrating the feasibility of the SHADOWS and NaNu experiments, substantially contributing to their proposal.

All these experiments target the intensity frontier, requiring a significant reduction of radiation background at up to 30 times higher instantaneous proton intensities than those delivered so far. Since muons constitute the dominant source of background, mitigation strategies were extensively analysed and developed. Magnetic muon shields based on magnetised iron blocks were identified as effective muon sweepers. Comprehensive design studies were conducted bringing their design from a theoretical concept to demonstrated feasibility, addressing integration requirements and beamline-specific challenges.

To further enhance the magnet design within the beamline's high-radiation environment, a novel AI-aided approach was developed. This method enables tailoring the magnet design to the specific background conditions in the cavern. The effectiveness of this method was demonstrated across multiple case studies presented in this thesis.