Uncovering the origins of mass: discovery of the di-higgs process and constraints on the higgs self-coupling
The Standard Model of particle physics describes the elementary constituents of matter and their interactions. In 2012, its last ingredient, the Higgs boson, was discovered at the Large Hadron Collider (LHC). The exploration of the Higgs boson is now one of the most exciting avenues to explore for New Physics beyond the Standard Model and allows some of the most pressing problems in theoretical physics to be addressed, such as the origins of the electroweak symmetry breaking mechanism. This important mechanism gives elementary particles their masses but the nature of this mechanism remains a mystery. 

A particularly crucial measurement is the production cross-section of Higgs boson pairs, which provides unique information on the Higgs self-coupling and on the underlying nature of the electroweak symmetry breaking mechanism. Most feasibility studies of the Higgs self-coupling conclude that there will be insufficient data for this measurement in the coming decade. However, my recent feasibility studies indicate that by using the Higgs pair production process with four bottom quarks in the final state, the discovery of the di-Higgs process and its cross section measurement can be made much earlier. This project aims to develop and complete the first measurement of the di-Higgs cross section and most stringent bounds on the Higgs self-coupling before 2023.
To achieve this goal I will develop new experimental techniques to improve the background reduction rates and enhance the signal. The objectives are the development of novel bottom quark energy reconstruction algorithms, new bottom quark and Higgs identification techniques, and neural network analysis tools. Analysis of ATLAS data will then enable searches for New Physics and ultimately the di-Higgs cross section measurement to constrain the Higgs self-coupling. This landmark measurement will lead to the confirmation of how particles acquire mass and open new avenues to understand what lies beyond the Standard Model.