The discovery of the Higgs Boson in 2012 has been followed by an immense body of research into the characteristics of this new particle. The diphoton decay channel offers a particularly attractive opportunity to examine the Higgs Boson in detail, given the excellent energy resolution of the ATLAS electromagnetic calorimeter. However, after collecting the full Run 2 data set, many Higgs Boson measurements are now at the point of being systematically limited, rather than statistically limited. I will give an overview of the Higgs Boson Couplings analysis in the diphoton channel, with a special focus on the recently observed top-associated production mode. I will then cover a number of approaches to reducing systematic uncertainties in this analysis and beyond, with particular emphasis on the use of Gaussian Processes, a machine learning technique uncommon within ATLAS.
Alden Fan / Christina Ignarra / Eric Miller
