Higgs Effective Theory to its limits

by Dr David Lopez-Vàl (UC Louvain)

Wednesday 10 Feb 2016, 14:00 → 15:00 Europe/Paris

Grande Salle du conseil

Effective field theory (EFT) provides an efficient framework to study the phenomenology of extended Higgs sectors at the LHC. One caveat is that, for the EFT to be valid, one needs to assume a clear hierarchy of scales. This is not obvious in an environment where partonic processes probe a wide range of scales. Moreover, a very large scale separation strongly suppresses the size of new physics accessible by the experiment. We examine these issues by considering several modifications of the Higgs sector: a singlet and doublet extension, scalar top partners, and a vector triplet. We systematically analyze how well the dimension-6 EFT in the linear representation describes LHC observables in comparison to the full theory, in a range where the LHC will be sensitive. We identify which situations potentially lead to sizable differences between full model and EFT-based predictions, and discuss their impact for Higgs measurements and their interpretation in the upcoming LHC run.

Transparents lopezval.pdf