The electroweak vacuum and di-Higgs production at the LHC
PT-CERN Call 2020/2
Universidade de Coimbra
Laboratório de Instrumentação e Física Experimental de Partículas
Since its discovery, the Higgs boson became a prime tool to search for physics beyond the Standard Model (SM). At the current level of precision, the Higgs boson is compatible with SM expectations. A number of open questions suggest the existence of new physics, that could be unveiled as we explore the LHC data. A wealth of experimental results from the ATLAS and CMS experiments, probe the region around the minimum of the Higgs potential, or vacuum. But the shape of this potential is not constrained experimentally. This shape is intimately connected to the breaking of the electroweak gauge symmetry, which resulted in the fundamental forces we experience today. To experimentally constrain this shape we must measure the Higgs boson selfcoupling, which is accessible at the LHC through the simultaneous production of two Higgs bosons. The selected student will join the Portuguese ATLAS team, working in close collaboration with theorists and integrated into our international collaboration. He or she will be able to contribute to enhancing our current knowledge in this important area, which will become one of the most important measurements of LHC experiments. The student will also employ the latest theory developments and the most recent advances in reconstruction techniques: from boosted object identification to machine learning. Part of this research will be done at the University of Birmingham, in the United Kingdom, in co-supervision with a colleague from the ATLAS collaboration. The successful student will be able to participate in the operation of the ATLAS experiment during the LHC Run 3 to start in 2021, and travel to CERN will be required.