Study of Higgs boson pair production and the trilinear Higgs boson self-coupling with the LHC Run 3 and beyond

Since the discovery of the Higgs boson (H) in 2012 by the CMS and ATLAS collaborations at the LHC, the high energy physics community has relentlessly worked on establishing the exact nature of this new fundamental particle. So far, this effort has managed to establish the main production and decay modes of the H boson accessible at the LHC. CMS has extensively measured the H boson mass and studied its spin and CP properties, and has found an astonishing level of agreement with the standard model of particle physics (SM). With recent advances in analysis techniques, one of the most important H boson properties, its self-coupling (λ) has entered the reach of experimental sensitivity, opening a direct window on the study of the Higgs potential itself. This project aims at expanding recent efforts in the study of Higgs boson pair production in the next LHC data taking period and beyond, to constrain λ even further and investigate a variety of theoretical models beyond the SM.