In the Standard Model of Particle Physics, the masses of particles are
generated through electroweak symmetry breaking, of which direct evidence was seen in 2012 with the discovery of the Higgs boson. However the question of whether this is the only Higgs boson, or part of a larger unexplored Higgs
sector, remains unanswered.
In this seminar I present the results of a two searches for extra charged Higgs
bosons, which naturally arises in several extensions of the Standard Model,
using 13.2 /fb and 36.1 /fb of pp collision data recorded by the ATLAS detector
during 2015 and 2016. The first result was originally presented at the summer
conference ICHEP in August 2016 and the second result was published as a JHEP paper.
The Higgs sector can be extended in other ways. For example Composite Higgs
models can be used to solve the fine tuning problem of the Higgs mass. These
models also predict Vector Like Quarks which can be searched for at the LHC.
Previous searches has only considered SM decays for the VLQs but we are
currenly working in collaboration with theorists on the phenomenology of BSM
decays where an additional pseudo Nambu-Goldstone boson S is introduced.