Axion-like Particle Search Using Machine Learning for the Signal Sensitivity Optimization with Run 2 LHC Data Recorded by the ATLAS Experiment

The neutral Standard Model Higgs boson was discovered in 2012 at CERN, and the search for further particles of extended models continues, in particular, the search for an axion-like particle (ALP). Using machine learning technologies, this analysis addresses the separation of ALP production from unwanted background reactions. In this project, the Run 2 data from the ATLAS detector are used and the efficiency as well as the significance of the machine learning algorithm are optimized as a function of the theoretical ALP mass. Abstract Published by the Jagiellonian University 2025 authors