Trigger Efficiencies for di-Higgs Production in the ATLAS Detector using Run-3 and Run-4 Simulations

This project evaluates the performance of the ATLAS Level-1 calorimeter for di-Higgs production, a key process for measuring the Higgs self-coupling. The efficiency of the four-jet multi-jet trigger was studied as a function of the di-Higgs mass and the transverse momentum of the fourth jet using simulated events under Run-3 and Run-4 conditions. Trigger emulation was performed, and events were filtered using jet triggers. While the efficiency is higher in the Run 4 scenario, this increase is primarily driven by a greater abundance of low-pT jets from pile-up. This result indicates that robust pile-up suppression techniques will be essential for effective multi-jet triggering in further upgrades of the ATLAS detector.